AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON MAY 7, 2002

                              Registration No. 333-

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM S-3

                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                        ADVANCED ENERGY INDUSTRIES, INC.
             (Exact name of registrant as specified in its charter)

                     DELAWARE                         84-0846841
         (State or other jurisdiction of            (IRS Employer
          incorporation or organization)        Identification Number)

                             1625 SHARP POINT DRIVE
                          FORT COLLINS, COLORADO 80525
                                 (970) 221-4670
          (Address, including postal or zip code, and telephone number,
        including area code, of registrant's principal executive offices)

                                MICHAEL EL-HILLOW
                SENIOR VICE PRESIDENT AND CHIEF FINANCIAL OFFICER
                        ADVANCED ENERGY INDUSTRIES, INC.
                             1625 SHARP POINT DRIVE
                          FORT COLLINS, COLORADO 80525
                                 (970) 221-4670
            (Name, address, including zip code, and telephone number,
                   including area code, of agent for service)

                                    Copy to:
                                JAY L. MARGULIES
                            THELEN REID & PRIEST LLP
                     333 WEST SAN CARLOS STREET, 17th FLOOR
                         SAN JOSE, CALIFORNIA 94110-2701
                                 (408) 282-1815

APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO THE PUBLIC: From time to
time after the effective date of this registration statement.

If the only securities being registered on this form are being offered pursuant
to dividend or interest reinvestment plans, please check the following box. [ ]

If any of the securities being registered on this Form are to be offered on a
delayed or continuous basis pursuant to Rule 415 under the Securities Act of
1933, other than securities offered solely in connection with dividend or
interest reinvestment plans, check the following box. [X]

If this Form is filed to register additional securities for an offering pursuant
to Rule 462(b) under the Securities Act, please check the following box and list
the Securities Act registration statement number of the earlier effective
registration statement for the same offering. [ ]

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under
the Securities Act, check the following box and list the Securities Act
registration statement number of the earlier effective registration statement
for the same offering. [ ]

If delivery of the prospectus is expected to be made pursuant to Rule 434,
please check the following box. [ ]

                         CALCULATION OF REGISTRATION FEE


     Title of Shares                                      Proposed Maximum          Proposed Maximum             Amount of
     to be Registered       Amount to be Registered   Aggregate Price Per Unit  Aggregate Offering Price      Registration Fee
     ----------------       -----------------------   ------------------------  ------------------------      ----------------
                                                                                                  
Common Stock, par value
$0.001 per share.                   120,000                   $31.82(1)               $3,818,400(1)               $351.29


(1) Estimated solely for the purpose of determining the registration fee in
accordance with Rule 457(c) under the Securities Act of 1933, as amended. The
above calculation is based on the average of the reported high and low prices of
Advanced Energy's Common Stock on the Nasdaq National Market on May 6, 2002.

                                   ----------

THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR DATES
AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL FILE
A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION STATEMENT
SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(a) OF THE
SECURITIES ACT OF 1933 OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME
EFFECTIVE ON SUCH DATE AS THE COMMISSION, ACTING PURSUANT TO SAID SECTION 8(a),
MAY DETERMINE.





THE INFORMATION IN THIS PROSPECTUS IS NOT COMPLETE AND MAY BE CHANGED. THESE
SECURITIES MAY NOT BE SOLD UNTIL THE REGISTRATION STATEMENT FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION IS EFFECTIVE. THIS PROSPECTUS IS NOT AN OFFER
TO SELL NOR DOES IT SEEK AN OFFER TO BUY THESE SECURITIES IN ANY STATE WHERE THE
OFFER OR SALE IS NOT PERMITTED.


                    SUBJECT TO COMPLETION, DATED MAY 7, 2002


PROSPECTUS


[ADVANCED ENERGY INDUSTRIES, INC. LOGO]

                                 120,000 Shares
                        Advanced Energy Industries, Inc.
                                  Common Stock
                          (Par Value $0.001 per share)

This prospectus relates to the resale of shares of common stock of Advanced
Energy Industries, Inc., a Delaware corporation, by Russell F. Jewett, the
selling holder named in this prospectus. In April 2002, we acquired the shares
of Litmas, a California corporation, we did not already own, through a merger of
Litmas with one of our wholly-owned subsidiaries. Mr. Jewett was the sole
shareholder of Litmas other than Advanced Energy. We acquired Mr. Jewett's
shares of Litmas stock in the merger and in exchange issued to Mr. Jewett
120,000 shares of Advanced Energy common stock. We will not receive any cash
proceeds from the sale of shares offered under this prospectus.

Up to 120,000 shares of the common stock offered hereby may be resold by Mr.
Jewett, the selling holder. The selling holder will receive all of the proceeds
from the sale of the securities and will pay any underwriting discounts and
selling commissions applicable to any sale. The selling holder and any
broker-dealers, agents or underwriters that participate in the distribution of
the securities may be "underwriters" within the meaning of the Securities Act of
1933, and any commission received by them and any profit on the resale of the
securities purchased by them may be underwriting commission or discounts under
the Securities Act.

We are paying all expenses of registration incurred in connection with this
offering, other than underwriter commissions and similar selling fees, any
transfer costs or any taxes owed upon any sales by the selling holder.

Our common stock is traded on the Nasdaq National Market under the symbol
"AEIS." The last reported sale price on May 6, 2002 was $31.25.

INVESTING IN ADVANCED ENERGY'S COMMON STOCK INVOLVES RISKS. SEE "RISK FACTORS"
ON PAGE 4 OF THIS PROSPECTUS.

NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY OTHER REGULATORY BODY HAS
APPROVED OR DISAPPROVED OF THESE SECURITIES OR PASSED UPON THE ACCURACY OR
ADEQUACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL
OFFENSE.


                  The date of this prospectus is May ___, 2002





                                Table of Contents



                                                                                                 Page
                                                                                              
       About this Prospectus                                                                      2
       Summary                                                                                    2
       Risk Factors                                                                               4
       Where You Can Find More Information                                                        4
       Cautionary Note on Forward-Looking Statements                                              5
       Use of Proceeds                                                                            6
       Selling Holder                                                                             6
       Plan of Distribution                                                                       7
       Legal Matters                                                                              8
       Experts                                                                                    9



                              ABOUT THIS PROSPECTUS


This document is called a prospectus and is part of a registration statement
that we filed with the Securities and Exchange Commission (the "SEC") using a
"shelf" registration or continuous offering process. Under this shelf process,
the selling holder may from time to time sell the securities described in this
prospectus in one or more offerings.


This prospectus provides you with a general description of the securities that
the selling holder may offer.


We will make copies of this prospectus available to the selling holder and have
informed him of the need to deliver copies of this prospectus to purchasers at
or prior to the time of any sale of the shares. To the extent required, this
prospectus may be amended or supplemented from time to time to describe a
specific plan of distribution. A prospectus supplement may also add, update or
change information in this prospectus. If there is any inconsistency between the
information in this prospectus and any prospectus supplement, you should rely on
the information in that prospectus supplement. You should read both this
prospectus and any prospectus supplement together with the additional
information described under the heading "Where You Can Find More Information."


We are not making an offer or soliciting a purchase of these securities in any
jurisdiction in which the offer or solicitation is not authorized or in which
the person making the offer or solicitation is not qualified to do so or to
anyone to whom it is unlawful to make the offer or solicitation.


The prospectus incorporates business, financial and risk information about us
that is not included in or delivered with this document. YOU MAY REQUEST AND
OBTAIN THIS INFORMATION FREE OF CHARGE BY WRITING OR TELEPHONING US AT THE
FOLLOWING ADDRESS: ADVANCED ENERGY INDUSTRIES, INC., 1625 SHARP POINT DRIVE,
FORT COLLINS, COLORADO 80525, ATTENTION: INVESTOR RELATIONS, TELEPHONE: (970)
221-4670.


                                     SUMMARY


The following summary is qualified in its entirety by the more detailed
information and historical consolidated financial statements, including the
notes to those financial statements, incorporated



                                       2


by reference herein. Investors should carefully consider the information set
forth under "Risk Factors" in the documents incorporated by reference herein.
Unless the context otherwise requires, the term "Advanced Energy" refers to
Advanced Energy Industries, Inc., and the terms "we," "us" and "our" refer to
Advanced Energy Industries, Inc., and its consolidated subsidiaries.


                        ADVANCED ENERGY INDUSTRIES, INC.


We design, manufacture and support a group of key subsystems for vacuum process
systems. Our customers use our products in plasma-based thin-film processing
equipment that is essential to the manufacture of semiconductors; compact disks,
DVDs and other digital storage media; flat-panel computer and television
screens; coatings for architectural glass and optics. We also manufacture power
supplies for advanced technology computer workstations.


Our direct current, or DC, and radio frequency, or RF, power systems refine,
modify and control the raw electrical power from a utility and convert it into
power that is uniform and predictable. This allows manufacturing equipment to
produce and deposit very thin films at an even thickness on a mass scale.
Moreover, through our acquisitions of Engineering Measurements Company in
January 2001 and Aera Japan Ltd. in January 2002, which provide gas flow
products, and Noah Holdings, Inc. in April 2000 and Sekidenko, Inc. in August
2000, which provide thermal control and measurement products, we are a company
that can provide high quality components and systems that bring together
technologies that provide our customers increased precision and productivity.


We market and sell our systems primarily to large, original equipment
manufacturers, or OEMs, of semiconductor, flat panel display, data storage and
other industrial thin film manufacturing equipment. We have sold our systems
worldwide to more than 100 OEMs and directly to more than 500 end-users. Our
principal customers include Applied Materials, Inc., Axcelis Technologies, Inc.,
Lam Research Corporation, Novellus Systems, Inc., ULVAC Technologies, Inc. and
The Unaxis Corporation. Sales to customers in the semiconductor capital
equipment industry comprised 59% of our sales in 2001, 70% in 2000 and 65% in
1999. We sell our systems primarily through direct sales personnel to customers
in the United States, Europe and Asia, and through distributors in various
regions outside the United States. International sales represented 36% of our
sales in 2001, 28% in 2000 and 27% in 1999.


DEVELOPMENT OF COMPANY BUSINESS


We incorporated in Colorado in 1981 and reincorporated in Delaware in 1995. In
1995, we effected the initial public offering of our common stock. Our executive
offices are located at 1625 Sharp Point Drive, Fort Collins, Colorado 80525, and
our telephone number is (970) 221-4670.


RECENT DEVELOPMENTS


On January 18, 2002, we completed our acquisition of Aera Japan Limited, a
Japanese corporation. The acquisition was effected through our subsidiary
AE-Japan, which purchased all of the outstanding stock of Aera. The aggregate
purchase price paid by AE-Japan was 5.73 billion Japanese yen (approximately $44
million, based upon an exchange rate of 130:1), which was funded from our
available cash. In connection with the acquisition, AE-Japan assumed
approximately $34 million of Aera's debt. Aera, which is headquartered in
Hachioji, Japan, has manufacturing facilities there and manufacturing, sales and
service offices in Austin, Texas; Dresden, Germany; Edinburgh, Scotland; and
Bundang, South Korea; and sales and service



                                       3


offices in Kirchheim, Germany; and Hshinchu, Taiwan. Aera supplies the
semiconductor capital equipment industry with product lines that include digital
mass flow controllers, pressure-based mass flow controllers, liquid mass flow
controllers, ultrasonic liquid flow meters and liquid vapor delivery systems.


On March 28, 2002, we acquired Dressler HF Technik GmbH, a privately owned
Germany-based provider of power supplies and matching networks, for a purchase
price of $16.75 million. We may pay an additional $3.25 million if Dressler is
able to achieve certain key business objectives by March 30, 2003.


Prior to April 2, 2002, we held a total ownership stake of 59.5% in Litmas, a
privately held, California corporation based in North Carolina which develops
and manufactures integrated power and plasma generating equipment. Litmas'
products are used for abating exhaust gasses from semiconductor equipment, as
plasma sources for manufacturing integrated circuits and fiber optics and as
emission sources for spectroscopy. On April 2, 2002, we acquired all of the
remaining outstanding shares of Litmas through a merger, in exchange for the
issuance of 120,000 shares of Advanced Energy common stock to Russell F. Jewett,
the sole shareholder of Litmas other than Advanced Energy. Litmas was founded in
1998.

On April 17, 2002, we reported our unaudited financial results for the first
quarter ended March 31, 2002. Revenues for the first quarter of 2002 were $42.9
million, including $6.7 million from Aera Japan Ltd., which we acquired in
January 2002. This represents a decrease of 43 percent from $74.7 million for
the first quarter of 2001, and an increase of 26 percent from $34.0 million for
the fourth quarter of 2001. Net loss for the first quarter of 2002 was $8.7
million, or $0.27 per share compared to first quarter 2001 net income of $5.1
million, or $0.16 per diluted share. This compares to the fourth quarter 2001
net loss of $14.4 million, or $0.45 per share.


THE OFFERING


This prospectus relates to the resale of shares of common stock of Advanced
Energy by Russell F. Jewett, the selling holder named in this prospectus. We
will not receive any cash proceeds from the sale of shares offered under this
prospectus.


Mr. Jewett may sell any or all of the 120,000 shares of the common stock covered
by this prospectus, or may choose not to sell any shares. He will pay any
underwriting discounts and selling commissions applicable to any sale.


                                  RISK FACTORS


Investing in our common stock involves a high degree of risk. Please see the
risk factors described in our Annual Report on Form 10-K for the year ended
December 31, 2001, which is incorporated by reference in this prospectus. Before
making an investment decision, you should carefully consider these risks as well
as other information contained or incorporated by reference in this prospectus.
The risks and uncertainties described are not the only ones facing us.
Additional risks and uncertainties not presently known to us or that we
currently deem immaterial may also impair our business operations. Before making
an investment decision, you should consult with your legal, tax and investment
advisers as to the effect to you of an investment in Advanced Energy common
stock.


                       WHERE YOU CAN FIND MORE INFORMATION


We have filed with the SEC a Registration Statement on Form S-3 under the
Securities Act, relating to the common stock being offered. This prospectus is
filed as part of the registration statement. Other parts of the registration
statement are omitted from this prospectus.



                                       4



We file annual, quarterly and special reports, proxy statements and other
information with the SEC. You may read and copy any document we file at the
SEC's Public Reference Room at 450 Fifth Street, N.W., Washington, D.C. 20549.
Please call the SEC at 1-800-SEC-0330 for further information on the operation
of the Public Reference Room. The SEC's website is located at www.sec.gov and
contains reports, proxy and information statements and other information
regarding issuers who file electronically. Our website is located at
www.advanced-energy.com, but the information on our website is not a part of
this prospectus.


In this document, we "incorporate by reference" the information we file with the
SEC, which means that we can disclose important information to you by referring
to that information. The information incorporated by reference is considered to
be part of this prospectus, and later information we file with the SEC will
update and supersede this information. We incorporate by reference the documents
listed below and any future filings made with the SEC under Section 13(a),
13(c), 14 or 15(d) of the Exchange Act until this offering is completed:


1. Our annual report on Form 10-K for the year ended December 31, 2001,
including the information incorporated by reference therein from our definitive
proxy statement relating to our 2002 annual meeting of stockholders;


2. Our current reports on Form 8-K and Form 8-K/A filed on February 1, 2002 and
April 2, 2002, respectively;

3. Our current reports on Form 8-K and Form 8-K/A filed on May 2, 2002 and
May 3, 2002, respectively; and

4. Our Form 8-A for registration of our common stock filed on October 12, 1995,
including any amendment or reports filed for the purpose of updating such
description.


You may obtain copies of these documents and filings, at no cost, by writing or
telephoning us at the following address: Advanced Energy Industries, Inc., 1625
Sharp Point Drive, Fort Collins, Colorado 80525, Attention: Investor Relations.
Telephone: (970) 221-4670.


YOU SHOULD RELY ONLY ON THE INFORMATION INCORPORATED BY REFERENCE OR PROVIDED IN
THIS PROSPECTUS. WE HAVE NOT AUTHORIZED ANYONE TO PROVIDE YOU WITH DIFFERENT
INFORMATION. YOU SHOULD NOT ASSUME THAT THE INFORMATION IN THIS PROSPECTUS,
INCLUDING ANY INFORMATION INCORPORATED HEREIN BY REFERENCE, IS ACCURATE AS OF
ANY DATE OTHER THAN THE DATE ON THE FRONT OF THE DOCUMENT.


                  CAUTIONARY NOTE ON FORWARD-LOOKING STATEMENTS


Some of the statements contained in or incorporated by reference in this
prospectus include "forward-looking statements" within the meanings of Section
27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act
of 1934. All statements contained or incorporated by reference in this
prospectus, other than statements of historical fact, are "forward-looking
statements." The words "anticipate," "believe," "estimate," "expect," "plan,"
"intend" and similar expressions are intended to identify these forward-looking
statements, but are not the exclusive means of identifying them. These
forward-looking statements reflect the current views of our management. However,
various risks, uncertainties and contingencies could cause our actual results,
performance or achievements to differ materially from those expressed in, or
implied by, these statements, including the following:


         o        customer inventory levels, needs and order levels;



                                       5


         o        our future revenues;


         o        our future gross profit;


         o        market acceptance of our products;


         o        research and development expenses;


         o        selling, marketing, general and administrative expenditures;


         o        capital resources sufficiency and availability;


         o        potential acquisitions;


         o        capital expenditures;


         o        restructuring activities and expenses;


         o        general economic conditions in the U.S. and worldwide; and


         o        the other risks and uncertainties discussed under the heading
                  "Risk Factors" and elsewhere in this prospectus and in the
                  documents incorporated by reference.


Our actual results could differ materially from those projected or assumed in
our forward-looking statements, because forward-looking statements by their
nature are subject to risks and uncertainties. Factors that could contribute to
these differences or prove our forward-looking statements, by hindsight, to be
overly optimistic or unachievable, include the factors described in this
section. Other factors, including factors which we do not now consider material,
also might contribute to the differences between our forward-looking statements
and our actual results. We assume no obligation to update any forward-looking
statement or the reasons why our actual results might differ.


                                 USE OF PROCEEDS


All of the shares of our common stock are being sold by the selling holder, who
will receive all of the net proceeds of any resales. We will not receive any
proceeds from the sale of these shares.


                                 SELLING HOLDER


We issued 120,000 shares to Mr. Jewett in connection with the acquisition of
Litmas on April 2, 2002, which occurred through a merger of Litmas with one of
our wholly-owned subsidiaries, LTM Acquisition Corporation, a California
corporation. As part of the acquisition, we undertook a contractual obligation
to file a registration statement covering the resale of the shares of Advanced
Energy common stock issued to Mr. Jewett.


Mr. Jewett, the selling holder, may from time to time offer and sell pursuant to
this prospectus any or all of the 120,000 shares of Advanced Energy common stock
received in the merger and covered by this prospectus. Mr. Jewett may also elect
not to sell any of those shares. The selling holder is not making any
representation that any shares covered by the prospectus will be offered for
sale. The selling holder reserves the right to accept or reject, in whole or in
part, any



                                       6


proposed sale of shares. When we refer to the "selling holder" in this
prospectus, we mean Mr. Jewett as well as the pledgees, donees, assignees,
transferees, successors and others who later hold any of the selling holder's
interests.


As of May 6, 2002, Mr. Jewett did not own beneficially any shares of common
stock of Advanced Energy or any of our convertible debt securities, other than
the shares covered by this prospectus. The 120,000 shares covered by this
prospectus represent less than one percent (1%) of the outstanding shares of
Advanced Energy. Mr. Jewett has indicated to us that he intends to retain and
not sell pursuant to this prospectus up to 90,000 of the shares. However, he is
not required to retain any shares and may choose at any time to sell such shares
pursuant to this prospectus. Because Mr. Jewett is free to sell all or any
portion of the shares offered hereby, we can make no estimate as to the amount
or percentage of the shares of common stock that will be held by the selling
holder upon termination of this offering.


Mr. Jewett has not had a material relationship with Advanced Energy within the
past three years other than as a director and executive officer of Litmas and as
a result of his ownership of Litmas shares prior to the acquisition by Advanced
Energy.


This prospectus also covers any additional shares of common stock that become
issuable in connection with the shares being registered by reason of any stock
dividend, stock split, recapitalization or other similar transaction effected
without the receipt of consideration which results in an increase in the number
of our outstanding shares of common stock.


                              PLAN OF DISTRIBUTION


We are registering all 120,000 shares on behalf of Mr. Jewett, the selling
holder. When we refer to the "selling holder" in this prospectus, we mean Mr.
Jewett as well as the pledgees, donees, assignees, transferees, successors and
others who later hold any of the selling holder's interests. We will not receive
proceeds from this offering. The selling holder will act independently of us in
making decisions with respect to the timing, manner and size of each sale.


The selling holder may offer and sell the shares from time to time directly to
purchasers. Alternatively, the selling holder may from time to time offer those
shares of common stock to or through underwriters, broker-dealers or agents, who
may receive compensation in the form of underwriting discounts, concessions or
commissions from the selling holders or the purchasers of the common stock for
whom they act as agents. These discounts, concessions or commissions as to any
particular underwriter, broker-dealer or agent may be in excess of those
customary in the types of transactions involved.


We have borne all fees and expenses incurred in connection with the registration
of the common stock. The selling holder will pay all expenses incident to the
offer and sale of the common stock, including any underwriting discounts,
selling commissions or fees, stock transfer taxes or similar costs. The selling
holder and any underwriters, broker-dealers or agents that participate in the
distribution of the common stock may be "underwriters" within the meaning of the
Securities Act, and any profit on the sale of such common stock and any
discounts, commissions, concessions or other compensation received by any such
underwriter, broker-dealer or agent may be underwriting discounts and
commissions under the Securities Act. Underwriters are subject to the prospectus
delivery requirements of the Securities Act.


The selling holder's common stock may be sold from time to time in one or more
transactions at fixed prices, at prevailing market prices at the time of sale,
at varying prices determined at the



                                       7


time of sale or at negotiated prices. The sale of the common stock may be
effected in transactions, which may involve block transactions:


         o on any national securities exchange or quotation service on which the
         common stock may be listed or quoted at the time of sale;


         o in the over-the-counter market;


         o in transactions otherwise than on such exchanges or in the
         over-the-counter market;


         o through the writing and exercise of options; or


         o through any other method permitted by applicable law, rule or
         regulation.


In connection with sales of the common stock or otherwise, the selling holder
may enter into hedging transactions with broker-dealers or others who may, in
turn, engage in short sales of the common stock in the course of hedging the
positions they assume. The selling holder may also sell the common stock short
and deliver common stock to close out short positions, or loan or pledge common
stock to broker-dealers or others who, in turn, may sell such securities.


In addition, any securities covered by this prospectus which qualify for sale
pursuant to Rule 144 promulgated under the Securities Act, may be sold under
Rule 144 rather than pursuant to this prospectus.


To comply with the securities laws of certain jurisdictions, if applicable, the
common stock will be offered or sold in such jurisdictions only through
registered or licensed brokers or dealers. In addition, in certain
jurisdictions, the common stock may not be offered or sold unless it has been
registered or qualified for sale in such jurisdictions or any exemption from
registration or qualification is available and is complied with.


The selling holder has advised us that he is neither a broker-dealer nor an
affiliate of a broker-dealer. The selling holder has also advised us that he has
not entered into any agreements, understandings or arrangements with any
underwriters or broker-dealers regarding the sale of his securities. There is no
underwriter or coordinating broker acting in connection with the proposed sale
of shares by the selling holder.


We will make copies of this prospectus available to the selling holder and have
informed him of the need for delivery of copies of this prospectus to purchasers
at or prior to the time of any sale of the shares. To the extent required, this
prospectus may be amended or supplemented from time to time to describe a
specific plan of distribution. The selling holder will be subject to certain
provisions of the Securities Exchange Act of 1934, as amended, including
Regulation M promulgated thereunder, which may limit the timing of purchase and
sales of our common stock by the selling holder.


                                  LEGAL MATTERS


The validity of the common stock will be passed upon for us by Thelen Reid &
Priest LLP, San Jose, California.



                                       8


                                     EXPERTS


The consolidated financial statements and schedule of Advanced Energy
Industries, Inc. as of December 31, 2001 and 2000 and for each of the three
years in the period ended December 31, 2001 incorporated by reference in this
prospectus and elsewhere in the registration statement have been audited by
Arthur Andersen LLP, independent public accountants, as indicated in their
reports with respect thereto, and are included herein in reliance upon the
authority of said firm as experts in giving said reports.


The financial statements of Aera Japan Limited as of and for the year ended June
30, 2001 incorporated in this prospectus by reference from Advanced Energy
Industries, Inc.'s Current Report on Form 8-K/A dated April 2, 2002 have been
audited by Deloitte Touche Tohmatsu, independent auditors, as stated in their
report, which is incorporated herein by reference, and have been so incorporated
in reliance upon the report of such firm given upon their authority as experts
in accounting and auditing.



                                       9


                                     PART II


                     INFORMATION NOT REQUIRED IN PROSPECTUS


ITEM 14. OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION


The following table sets forth an estimate of the expenses to be incurred by the
Advanced Energy in connection with the issuance and distribution of the
securities being registered:




                                                             Amount to be Paid
                                                             -----------------
                                                          
SEC Registration Statement Filing Fee                        $   352

Legal Fees and Expenses                                      $10,000

Accounting Fees and Expenses                                 $10,000*

Printing                                                     $ 1,000*

Miscellaneous                                                $ 2,500*
                                                             -------

                  Total                                      $23,852*
                                                             =======



*Estimate.


ITEM 15. INDEMNIFICATION OF DIRECTORS AND OFFICERS


As permitted by the Delaware General Corporation Law ("DGCL"), Advanced Energy's
Restated Certificate of Incorporation, as amended (the "AE Certificate"),
provides that no director shall be personally liable to Advanced Energy or any
stockholder for monetary damages for breach of fiduciary duty as a director,
except for liability: (i) for any breach of the duty of loyalty to Advanced
Energy or its stockholders; (ii) for acts or omissions not in good faith or
involving intentional misconduct or a knowing violation of the law; (iii) under
Section 174 of the DGCL; or (iv) for any transaction from which the director
derived an improper personal benefit. While the AE Certificate provides
protection from awards for monetary damages for breaches of fiduciary duty, it
does not eliminate the director's duty of care. Accordingly, the AE Certificate
will not affect the availability of equitable remedies, such as an injunction,
based on a director's breach of the duty of care. The provisions of the AE
Certificate described above apply to officers of Advanced Energy only if they
are directors of Advanced Energy and are acting in their capacity as directors,
and does not apply to officers of Advanced Energy who are not directors.


In addition, Advanced Energy's Bylaws provide that Advanced Energy shall
indemnify its Executive Officers (as defined in Rule 3b-7 promulgated under the
Exchange Act) and directors, and any employee who serves as an Executive Officer
or director of any corporation at Advanced Energy's request, to the fullest
extent permitted under and in accordance with the DGCL; provided, however, that
Advanced Energy may modify the extent of such indemnification by individual
contracts with its Executive Officers and directors; and, provided further, that
Advanced Energy shall not be required to indemnify any Executive Officer or



                                      II-1


director in connection with any proceeding (or part thereof) initiated by such
person unless: (i) such indemnification is expressly required to be made by law;
(ii) the proceeding was authorized by the directors of Advanced Energy; (iii)
such indemnification is provided by Advanced Energy, in its sole discretion,
pursuant to the powers vested in Advanced Energy under the DGCL; or (iv) such
indemnification is required to be made under Article XI, Section 43, Subsection
(d) of Advanced Energy's Bylaws. Under the DGCL, directors and officers as well
as employees and individuals may be indemnified against expenses (including
attorneys' fees), judgments, fines and amounts paid in settlement in connection
with specified actions, suits or proceedings, whether civil, criminal,
administrative or investigative (other than an action by or in the right of the
corporation as a derivative action) if they acted in good faith and in a manner
they reasonably believed to be in or not opposed to the best interests of the
corporation, and with respect to any criminal action or proceeding, had no
reasonable cause to believe their conduct was unlawful. Advanced Energy
maintains a policy of directors' and officers' liability insurance that insures
Advanced Energy's directors and officers against the costs of defense,
settlement or payment of a judgment under certain circumstances.


ITEM 16. EXHIBITS


The following is a list of Exhibits filed as part of the Registration Statement:


Exhibit Number            Description of Document

4.1                       Restated Certificate of Incorporation, as amended(1)

4.2                       Bylaws(2)

5.1                       Opinion of Thelen Reid & Priest LLP

23.1                      Consent of Arthur Andersen LLP

23.2                      Consent of Deloitte Touche Tohmatsu

23.3                      Consent of Thelen Reid & Priest LLP(3)

24.1                      Power of Attorney(4)

(1) Incorporated by reference from Advanced Energy's Quarterly Report on Form
10-Q for the quarter ended June 30, 2001, filed August 13, 2001 (File No.
000-26966).

(2) Incorporated by reference from Advanced Energy's Registration Statement on
Form S-1, filed September 20, 1995, as amended (File No. 33-97188).

(3) Included in Exhibit 5.1.

(4) Included on the signature pages to this  Registration Statement.


ITEM 17. UNDERTAKINGS


The undersigned Registrant hereby undertakes:


(1) To file, during any period in which offers or sales are being made, a
post-effective amendment to this registration statement;


(i) To include any prospectus required by Section 10(a)(3) of the Securities Act
of 1933;



                                      II-2


(ii) To reflect in the prospectus any facts or events arising after the
effective date of the registration statement (or the most recent post-effective
amendment thereof) which, individually or in the aggregate, represent a
fundamental change in the information set forth in the registration statement.
Notwithstanding the foregoing, any increase or decrease in volume of securities
offered (if the total dollar value of securities offered would not exceed that
which was registered) and any deviation from the low or high end of the
estimated maximum offering range may be reflected in the form of prospectus
filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the
changes in volume and price represent no more than a 20 percent change in the
maximum aggregate offering price set forth in the "Calculation of Registration
Fee" table in the effective registration statement;


(iii) To include any material information with respect to the plan of
distribution not previously disclosed in the registration statement or any
material change to such information in the registration statement;


provided, however, that paragraphs (1)(i) and (1)(ii) of this section do not
apply if the registration statement is on Form S-3 and the information required
to be included in a post- effective amendment by those paragraphs is contained
in periodic reports filed with or furnished to the Commission by the registrant
pursuant to section 13 or section 15(d) of the Securities Exchange Act of 1934
that are incorporated by reference in the registration statement.


(2) That, for the purpose of determining any liability under the Securities Act
of 1933, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.


(3) To remove from registration by means of a post- effective amendment any of
the securities being registered which remain unsold at the termination of the
offering.


The undersigned Registrant hereby undertakes that, for the purposes of
determining any liability under the Securities Act of 1933, each filing of the
registrant's annual report pursuant to section 13(a) or section 15(d) of the
Securities Exchange Act of 1934 that is incorporated by reference in the
registration statement shall be deemed a new registration statement relating to
the securities offered therein, and the offering of such securities at that time
shall be deemed to be the initial bona fide offering thereof.


Insofar as indemnification for liabilities arising under the Securities Act of
1933 may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant
has been advised that in the opinion of the Securities and Exchange Commission
such indemnification is against public policy as expressed in the Act, and is,
therefore, unenforceable. In the event that a claim for indemnification against
such liabilities (other than payment by the Registrant of expenses incurred or
paid by a director, officer or controlling person of the Registrant in the
successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Act and will be governed by the final adjudication of
such issue.



                                      II-3


                                   SIGNATURES


Pursuant to the requirements of the Securities Act of 1933, the registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-3 and has duly caused this registration
statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Fort Collins, State of Colorado, on May 6, 2002.


ADVANCED ENERGY INDUSTRIES, INC.



By: /s/ DOUGLAS S. SCHATZ
    ---------------------
Name: Douglas S. Schatz
Title: President, Chief Executive Officer and Chairman of the Board


Pursuant to the requirements of the Securities Act of 1933, this registration
statement has been signed by the following persons in the capacities and on the
date indicated.


POWER OF ATTORNEY


Each person whose signature appears below hereby appoints Douglas S. Schatz and
Michael El-Hillow, and each of them severally, acting alone and without the
other, his true and lawful attorney-in-fact with authority to execute in the
name of each such person, and to file with the Securities and Exchange
Commission, together with any exhibits thereto and other documents therewith,
any and all amendments (including without limitation post-effective amendments)
to this registration statement, necessary or advisable to enable the Registrant
to comply with the Securities Act and any rules, regulations and requirements of
the Securities and Exchange Commission in respect thereof, which amendments may
make such changes in this registration statement as the aforesaid
attorney-in-fact deems appropriate.


/s/ DOUGLAS S. SCHATZ                       Date: May 6, 2002
---------------------
Douglas S. Schatz
President, Chief Executive Officer
and Chairman of the Board
(Principal Executive Officer)


/s/ MICHAEL EL-HILLOW                       Date: May 6, 2002
---------------------
Michael El-Hillow
Senior Vice President and
Chief Financial Officer
(Principal Financial and Accounting Officer)





/s/ G. BRENT BACKMAN                        Date: May 6, 2002
--------------------
G. Brent Backman
Director


/s/ RICHARD P. BECK                         Date: May 6, 2002
-------------------
Richard P. Beck
Director


/s/ TRUNG T. DOAN                           Date: May 6, 2002
-----------------
Trung T. Doan
Director


/s/ ARTHUR A. NOETH                         Date: May 6, 2002
-------------------
Arthur A. Noeth
Director


/s/ ELWOOD SPEDDEN                          Date: May 6, 2002
------------------
Elwood Spedden
Director


/s/ GERALD M. STAREK                        Date: May 6, 2002
--------------------
Gerald M. Starek
Director


/s/                                         Date: May __, 2002
-------------------------
Arthur W. Zafiropoulo
Director





                                  EXHIBIT INDEX




EXHIBIT
NUMBER                    DESCRIPTION
------                    -----------
                       
4.1                       Restated Certificate of Incorporation, as amended(1)

4.2                       Bylaws(2)

5.1                       Opinion of Thelen Reid & Priest LLP

23.1                      Consent of Arthur Andersen LLP

23.2                      Consent of Deloitte Touche Tohmatsu

23.3                      Consent of Thelen Reid & Priest LLP(3)

24.1                      Power of Attorney(4)



(1) Incorporated by reference from Advanced Energy's Quarterly Report on Form
10-Q for the quarter ended June 30, 2001, filed August 13, 2001 (File No.
000-26966).

(2) Incorporated by reference from Advanced Energy's Registration Statement on
Form S-1, filed September 20, 1995, as amended (File No. 33-97188).

(3) Included in Exhibit 5.1.

(4) Included on the signature pages to this  Registration Statement.