EXHIBIT 4.1



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                               THE AES CORPORATION

                                       AND

                         BANK ONE, NATIONAL ASSOCIATION

             (FORMERLY KNOWN AS THE FIRST NATIONAL BANK OF CHICAGO)


                                   as Trustee

                               ------------------

                          FOURTH SUPPLEMENTAL INDENTURE

                          Dated as of December 20, 2000

                                       TO

                                SENIOR INDENTURE

                          Dated as of December 8, 1998

                               ------------------



                           8.75% Senior Notes due 2002


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     The Fourth Supplemental INDENTURE, is dated as of this 20th day of
December, 2000 (the "Fourth Supplemental Indenture"), between THE AES
CORPORATION, a corporation duly organized and existing under the laws of the
State of Delaware (hereinafter sometimes referred to as the "Company"), and BANK
ONE, NATIONAL ASSOCIATION (formerly known as THE FIRST NATIONAL BANK OF
CHICAGO), a national banking association, as trustee (hereinafter sometimes
referred to as the "Trustee").

     WHEREAS, the Company entered into a Senior Indenture dated as of December
8, 1998 between the Company and the Trustee (the "Indenture") to provide for the
future issuance of its senior debentures, notes or other evidences of
indebtedness (collectively, the "Securities"), said Securities to be issued from
time to time in series as might be determined by the Company pursuant to the
Indenture and, in an unlimited aggregate principal amount; and

     WHEREAS, pursuant to the terms of the Indenture, the Company desires to
provide for the establishment of a new series of its Securities to be known as
its 8.75% Senior Notes due 2002 (said series being hereinafter referred to as
the "Series D Senior Notes"), the form and substance of such Series D Senior
Notes and the terms, provisions and conditions thereof to be set forth as
provided in the Indenture and this Fourth Supplemental Indenture; and

     WHEREAS, the Company desires and has requested the Trustee to join with it
in the execution and delivery of this Fourth Supplemental Indenture, and all
requirements necessary to make this Fourth Supplemental Indenture a valid
instrument, in accordance with its terms, and to make the Series D Senior Notes,
when executed by the Company and authenticated and delivered by the Trustee, the
valid obligations of the Company;

     NOW, THEREFORE, in consideration of the purchase and acceptance of the
Series D Senior Notes by the Holders thereof, and for the purpose of setting
forth, as provided in the Indenture, the form and substance of the Series D
Senior Notes and the terms, provisions and conditions thereof, the Company
covenants and agrees with the Trustee as follows:


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                                  ARTICLE ONE

             DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION

     SECTION 1.1. TERMS DEFINED IN THE INDENTURE.

     Each capitalized term used not but defined in this Fourth Supplemental
Indenture shall have the meaning assigned to such term in the Indenture.

     SECTION 1.2. CERTAIN DEFINITIONS.

     The following definitions are hereby added to the definitions contained in
Section 1.1 of the Indenture, but only with respect to the Series D Senior Notes
issued in accordance with the provisions hereof:

     "Attributable Debt" means the present value (discounted at the rate of
8.75% per annum compounded monthly) of the obligations for rental payments
required to be paid during the remaining term of any lease of more than 12
months.

     "Consolidated Net Assets" means the aggregate amount of assets (less
reserves and other deductible items) after deducting current liabilities, as
shown on the consolidated balance sheet of the Company and its Subsidiaries
contained in the latest annual report to the stockholders of the Company and
prepared in accordance with GAAP.

     "DTC" shall have the meaning provided in Section 2.1 hereof.

     "Funded Debt" means indebtedness for borrowed money having a maturity of,
or by its terms extendible or renewable for, a period of more than 12 months
after the determination of the amount thereof.

     "Principal Property" means any building, structure or other facility
(together with the land on which it is erected and fixtures comprising a part
thereof) used primarily for manufacturing, processing, research, warehousing or
distribution, owned or leased by the Company and having a net book value in
excess of 2% of Consolidated Net Assets, other than any such building, structure
or other facility or portion thereof which is a pollution control facility
financed by state or local governmental obligations or which the principal
executive officer, president and principal financial officer of the Company
determine in good faith is not of material importance to the total business
conducted or assets owned by the Company and its Subsidiaries as an entirety.




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                                  ARTICLE TWO

                            THE SERIES D SENIOR NOTES

     SECTION 2.1. FORM.

     The Series D Senior Notes shall be substantially in the form of Exhibit A
hereto, which is a part of this Fourth Supplemental Indenture, with such
appropriate insertions, omissions, substitutions and other variations as are
required or permitted by the Indenture and this Fourth Supplemental Indenture,
and may have such letters, numbers or other marks of identification and such
legends or endorsements placed thereon as may be required to comply with the
rules of any securities exchange or as may, consistently herewith, be determined
by the Officers of the Company executing such Series D Senior Notes, as
evidenced by their execution of the Series D Senior Notes.

     The Series D Senior Notes will initially be issued as Registered Global
Securities.

     The Company initially appoints The Depository Trust Company ("DTC") and the
Trustee to act as Depositary and custodian, respectively, with respect to the
Series D Senior Notes.

     The Company initially appoints the Trustee to act as Paying Agent and
Registrar with respect to the Series D Senior Notes.

     SECTION 2.2. DESIGNATION AND AMOUNT.

          (a) The Series D Senior Notes shall be entitled the "8.75% Senior
     Notes due 2002" of the Company.

          (b) The Trustee shall authenticate and deliver Series D Senior Notes
     for original issue on the date hereof in an aggregate principal amount of
     $300,000,000. The aggregate principal amount of Series D Senior Notes that
     may be authenticated and delivered under the Indenture may not exceed the
     amount set forth in the foregoing sentence, except for Series D Senior
     Notes that may be authenticated and delivered upon registration of transfer
     of, or in exchange for, or in lieu of, other Series D Senior Notes pursuant
     to Sections 2.7, 2.8, 2.10, 3.3 or 9.4 of the Indenture.

          (c) The Company may not issue new Series D Senior Notes to replace
     Series D Senior Notes that it has paid or delivered to the Trustee for
     cancellation.

     SECTION 2.3. INTEREST.

     Interest on the Series D Senior Notes shall be payable in the amount, on
the dates and in the manner provided for in the form of the Series D Senior Note
attached hereto as Exhibit A.


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     SECTION 2.4. DENOMINATIONS.

     The Series D Senior Notes shall be Registered Securities in denominations
of $1,000 or any integral multiple thereof.

     SECTION 2.5. PLACE OF PAYMENT.

     The place of payment for the Series D Senior Notes shall be the Borough of
Manhattan, The City of New York. So long as the Series D Senior Notes are in the
form of Registered Global Securities, the Company agrees that payments of
interest on, and any portion of the Principal of, the Series D Senior Notes
shall be made by the Paying Agent, upon receipt from the Company of immediately
available funds, directly to the Depositary (by Federal funds wire transfer).

                                  ARTICLE THREE

                                   [RESERVED]

                                  ARTICLE FOUR

                         ADDITIONAL COVENANTS APPLICABLE
                          TO THE SERIES D SENIOR NOTES

     SECTION 4.1. RESTRICTIONS ON SECURED DEBT.

     If the Company shall incur, issue, assume or guarantee any indebtedness for
borrowed money represented by notes, bonds, debentures or other similar
evidences of indebtedness, secured by a mortgage, pledge or other lien on any
Principal Property or any capital stock or indebtedness held directly by the
Company of any Subsidiary of the Company, the Company shall secure the Series D
Senior Notes equally and ratably with (or prior to) such indebtedness, so long
as such indebtedness shall be so secured, unless after giving effect thereto the
aggregate amount of all such indebtedness so secured, together with all
Attributable Debt in respect of sale and leaseback transactions involving
Principal Properties, would not exceed 15% of the Consolidated Net Assets of the
Company.

     The foregoing restriction shall not apply to, and there shall be excluded
in computing secured indebtedness for the purpose of such restriction,
indebtedness secured by (a) property of any Subsidiary of the Company, (b) liens
on property of, or on any shares of stock or debt of, any corporation existing
at the time such corporation becomes a Subsidiary, (c) liens in favor of the
Company or any Subsidiary, (d) liens in favor of U.S. or foreign governmental
bodies to secure partial, progress, advance or other payments, (e) liens on
property, shares of stock or debt existing at the time of acquisition thereof
(including acquisition through merger or consolidation), purchase money
mortgages and construction cost mortgages existing at or incurred within 180
days of the time of acquisition thereof, (f) liens existing on the first date on
which any Series D Senior Note is authenticated by the Trustee, (g) liens under
one or more credit facilities for indebtedness in an aggregate principal amount
not to exceed $900,000,000 at any time outstanding, (h) liens incurred in
connection with pollution control, industrial revenue


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or similar financings, and (i) any extension, renewal or replacement of any debt
secured by any liens referred to in the foregoing clauses (a) through (h),
inclusive.

     SECTION 4.2. RESTRICTIONS ON SALES AND LEASEBACKS.

     The Company shall not enter into any sale and leaseback transaction
involving any Principal Property, the acquisition or completion of construction
and commencement of full operation of which has occurred more than 180 days
prior thereto, unless (a) the Company could incur a lien on such property under
the restrictions described in Section 4.1 hereof in an amount equal to the
Attributable Debt with respect to the sale and leaseback transaction without
equally and ratably securing the Series D Senior Notes or (b) the Company,
within 180 days after the sale or transfer by the Company, applies to the
retirement of its Funded Debt an amount equal to the greater of (i) the net
proceeds of the sale of the Principal Property sold and leased pursuant to such
arrangement or (ii) the fair market value of the Principal Property so sold and
leased as determined by the board of directors of the Company; provided that the
amount to be applied to the retirement of Funded Debt of the Company shall be
reduced by (A) the principal amount of any Series D Senior Notes delivered
within 180 days after such sale or transfer to the Trustee for retirement and
cancellation, and (B) the principal amount of Funded Debt, other than Series D
Senior Notes, voluntarily retired by the Company within 180 days after such sale
or transfer; provided further that no retirement referred to in this clause (b)
may be effected by payment at maturity or pursuant to any mandatory sinking fund
payment or any mandatory prepayment provision.

                                  ARTICLE FIVE

                     ADDITIONAL EVENTS OF DEFAULT APPLICABLE
                           TO THE SERIES D SENIOR NOTE

     SECTION 5.1. ADDITIONAL EVENTS OF DEFAULT.

     Pursuant to Section 6.1 (f) of the Indenture, an "Event of Default" shall
be deemed to occur with respect to the Series D Senior Notes if an event of
default, as defined in any indenture or instrument evidencing or under which the
Company has as of the date of this Fourth Supplemental Indenture or shall
thereafter have outstanding any indebtedness, shall happen and be continuing and
either (a) such default results from the failure to pay the principal of such
indebtedness in excess of $50 million at final maturity of such indebtedness or
(b) as a result of such default the maturity of such indebtedness shall have
been accelerated so that the same shall be or become due and payable prior to
the date on which the same would otherwise have become due and payable, and such
acceleration shall not be rescinded or annulled within 60 days and the principal
amount of such indebtedness, together with the principal amount of any other
indebtedness of the Company in default, or the maturity of which has been
accelerated, aggregates $50 million or more; provided that the Trustee shall not
be charged with knowledge of any such default unless written notice thereof
shall have been given to the Trustee by the Company, by the holder or an agent
of the holder of any such indebtedness, by the trustee then acting under any
indenture or other instrument under which such default shall have occurred, or
by the holders of not less than 25% in the aggregate principal amount of the
Series D Senior Notes at the time outstanding; and provided further that if such
default shall be remedied or


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cured by the Company or waived by the holder of such indebtedness, then the
Event of Default described under this Fourth Supplemental Indenture shall be
deemed likewise to have been remedied, cured or waived without further action on
the part of the Trustee, any Holder of Series D Senior Notes or any other
person.

                                  ARTICLE SIX

                            MISCELLANEOUS PROVISIONS

     SECTION 6.1. RATIFICATION.

     The Indenture, as supplemented by this Fourth Supplemental Indenture, is in
all respects ratified and confirmed. This Fourth Supplemental Indenture shall be
deemed part of the Indenture in the manner and to the extent provided herein and
therein.

     SECTION 6.2. COUNTERPARTS.

     This Fourth Supplemental Indenture may be executed in any number of
counterparts each of which shall be an original; but such counterparts shall
together constitute but one and the same instrument.


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     IN WITNESS WHEREOF, the parties hereto have caused this Fourth Supplemental
Indenture to be duly executed and attested, on the date or dates indicated in
the acknowledgments and as of the day and year first above written.

                                          THE AES CORPORATION, as
                                          the Company

                                          By:_________________________________
                                               Name:
                                               Title:
Attest:

By:_______________________
     Name :
     Title:

                                          BANK ONE, NATIONAL ASSOCIATION
                                          (formerly known as THE FIRST
                                          NATIONAL BANK OF CHICAGO), as Trustee


                                          By:_________________________________

                                               Name:
                                               Title:

Attest:


By:_______________________
    Name:
    Title:


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                                                                       EXHIBIT A

                     [FORM OF FACE OF SERIES D SENIOR NOTE]

           [INSERT IF THE NOTE IS TO BE A REGISTERED GLOBAL SECURITY]

     This Series D Senior Note is a Registered Global Security within the
meaning of the Indenture hereinafter referred to and is registered in the name
of a Depositary or a nominee of a Depositary. This Series D Senior Note is
exchangeable for Series D Senior Notes registered in the name of a person other
than the Depositary or its nominee only in the limited circumstances described
in the Indenture. Unless and until it is exchanged in whole or in part for
Securities in definitive registered form, this Security may not be transferred
except as a whole by the Depositary to the nominee of the Depositary or by a
nominee of the Depositary to the Depositary or another nominee of the Depositary
or by the Depositary or any such nominee to a successor Depositary or a nominee
of such successor Depositary.

     Unless this Series D Senior Note is presented by an authorized
representative of The Depository Trust Company (55 Water Street, New York, New
York) to the issuer or its agent for registration of transfer, exchange or
payment, and any Series D Senior Note issued is registered in the name of Cede &
Co. or such other name as requested by an authorized representative of The
Depository Trust Company and any payment hereon is made to Cede & Co., ANY
TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY A PERSON IS
WRONGFUL since the registered owner hereof, Cede & Co., has an interest herein.


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No.                                                             CUSIP NO.:00130H


                                  $300,000,000

                           8.750% SENIOR NOTE DUE 2002


                       THE AES CORPORATION promises to pay
                     to Cede & Co or registered assigns the
        principal sum of three hundred million Dollars ($300,000,000) on
                                December 15, 2002

Interest Payment Dates: December 15 and June 15 of each year, commencing June
15, 2001

Record Dates:  The fifteenth calendar day prior to each Interest Payment Date.


                                                   By:________________________
                                                        Authorized Signature

                                                   By:________________________
                                                        Authorized Signature

Dated:  December 20, 2000

Certificate of Authentication

     This is one of the 8.750% Senior Notes due 2002 referred to in the
within-mentioned Indenture.

                                               Bank One, National Association
                                               (formerly known as The First
                                               National Bank of Chicago),
                                               as Trustee


                                               By:____________________________
                                                        Authorized Signatory


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                               THE AES CORPORATION

                          SERIES D SENIOR NOTE DUE 2002

     1. Interest. THE AES CORPORATION, a Delaware corporation (the "Company,"
which definition shall include any successor thereto in accordance with the
Indenture (as defined below), promises to pay, until the principal hereof is
paid or made available for payment, interest on the principal amount set forth
on the reverse side hereof at a rate of 8.75% per annum. Interest on the Series
D Senior Notes will accrue from and including the most recent date to which
interest has been paid or, if no interest has been paid, from December 20, 2000
through but excluding the date on which interest is paid. Interest shall be
payable in arrears on December 15 and June 15 of each year (each an "Interest
Payment Date"), commencing June 15, 2001. Interest will be computed on the basis
of a 360-day year of twelve 30-day months.

     2. Method of Payment. The Company will pay interest on the Series D Senior
Notes (except defaulted interest) to the Persons who are registered Holders of
Series D Senior Notes at the close of business on the fifteenth calendar day
prior to each Interest Payment Date (each, a "Regular Record Date"). Holders
must surrender Series D Senior Notes to a Paying Agent to collect principal
payments. The Company will pay principal and interest in money of the United
States that at the time of payment is legal tender for payment of public and
private debts. At the Company's option, interest may be paid by check mailed to
the registered address of the Holder of this Series D Senior Note.

     3. Paying Agent and Registrar. Initially, Bank One, National Association
(formerly known as The First National Bank of Chicago) (the "Trustee") will act
as Paying Agent and Registrar. The Company may change any Paying Agent,
Registrar or co-Registrar without notice.

     4. Indenture. The Company issued the Series D Senior Notes under an
Indenture dated as of December 8, 1998 between the Company and the Trustee as
supplemented by the Fourth Supplemental Indenture dated as of December 20, 2000
between the Company and the Trustee (said Indenture, as so supplemented, the
"Indenture"). This Series D Senior Note is one of an issue of Securities of the
Company issued under the Indenture. The terms of the Series D Senior Notes
include those stated in the Indenture and those made part of the Indenture by
reference to the Trust Indenture Act of 1939 (15 U.S. Code ss.ss.77aaa-77bbbb)
as amended from time to time. The Series D Senior Notes are subject to all such
terms, and Holders of the Series D Senior Notes are referred to the Indenture
and such Act for a statement of them. Capitalized terms used herein and not
otherwise defined have the meanings set forth in the Indenture. The Series D
Senior Notes are general unsecured and unsubordinated obligations of the Company
ranking pari passu with all of

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the Company's unsecured and unsubordinated obligations, limited in aggregate
principal amount to $300,000,000. The Indenture limits the ability of the
Company to incur certain secured indebtedness and to enter into certain sale and
leaseback transactions.

     5. [RESERVED]

     6. Denominations, Transfer, Exchange. The Series D Senior Notes are in
registered form without coupons in denominations of $1,000 and integral
multiples of $1,000. A Holder may transfer or exchange Series D Senior Notes in
accordance with the Indenture. The Registrar may require a Holder, among other
things, to furnish appropriate endorsements and transfer documents and to pay to
it any taxes and fees required by law or permitted by the Indenture. The
Registrar need not transfer or exchange any Series D Senior Notes or portion of
a Series D Series Note selected for redemption, or transfer or exchange any
Series D Series Notes for a period of 15 days before selection of such Series D
Series Notes to be redeemed.

     7. Persons Deemed Owners. The registered holder of a Series D Senior Note
may be treated as the owner of it for all purposes.

     8. Unclaimed Money. If money for the payment of principal or interest
remains unclaimed for two years, the Trustee or Paying Agent will pay the money
back to the Company at its written request. After that, Holders entitled to the
money must look to the Company for payment as general creditors unless an
"abandoned property" law designates another Person.

     9. Amendment, Supplement, Waiver. The Company and the Trustee may, without
the consent of the holders of any outstanding Series D Senior Notes, amend,
waive or supplement the Indenture or the Series D Senior Notes for certain
specified purposes, including, among other things, curing ambiguities, defects
or inconsistencies, maintaining the qualification of the Indenture under the
Trust Indenture Act of 1939 or making any other change that does not adversely
affect the rights of any Holder in any material respect. Other amendments and
modifications of the Indenture or the Series D Senior Notes may be made by the
Company and the Trustee with the consent of the Holders of not less than a
majority of the aggregate principal amount of the outstanding Securities of all
series affected, subject to certain exceptions requiring the consent of the
Holders of the particular Series D Senior Notes.

     10. Successor Corporation. When a successor corporation assumes all the
obligations of its predecessor under the Series D Senior Notes and the Indenture
and the transaction complies with the terms of Article 5 of the Indenture, the
predecessor corporation, subject to certain exceptions, will be released from
those obligations.

     11. Defaults and Remedies. Events of Default are set forth in the
Indenture. Subject to certain limitations in the Indenture, if an Event of

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     Default (other than an Event of Default specified in Section 6.1(d) or (e)
of the Indenture with respect to the Company) occurs and is continuing, then the
holders of not less than 25% in aggregate principal amount of the outstanding
Series D Senior Notes may, or the Trustee may, declare the principal of, plus
accrued interest, if any, to be due and payable immediately. If an Event of
Default specified in Section 6.1(d) or (e) of the Indenture with respect to the
Company occurs and is continuing, the principal of and accrued interest on all
of the Series D Senior Notes shall ipso facto become and be immediately due and
payable without any declaration or other act on the part of the Trustee or any
Holder. Holders of Series D Senior Notes may not enforce the Indenture or the
Series D Senior Notes except as provided in the Indenture. The Trustee may
require indemnity reasonably satisfactory to it before it enforces the Indenture
or the Series D Senior Notes. Subject to certain limitations, Holders of a
majority in principal amount of the then outstanding Series D Senior Notes may
direct the Trustee in its exercise of any trust or power. The Trustee may
withhold from Holders of the Series D Senior Notes notice of any continuing
default (except a default in payment of principal or interest or a failure to
comply with Article 5 of the Indenture) if it determines in good faith that
withholding notice is in their interests. The Company must furnish an annual
compliance certificate to the Trustee.

     12. Trustee Dealing with Company. The Trustee, in its individual or any
other capacity, may make loans to, accept deposits from, and perform services
for the Company or its Affiliates, and may otherwise deal with the Company or
its Affiliates, as if it were not Trustee.

     13. No Recourse Against Others. A director, officer, employee, stockholder
or beneficiary, as such, of the Company shall not have any liability for any
obligations of the Company under the Series D Senior Notes or the Indenture or
for any claim based on, in respect of or by reason of, such obligations or their
creation. Each Holder of the Series D Senior Notes by accepting a Series D
Senior Note waives and releases all such liability. The waiver and release are
part of the consideration for the issue of the Series D Senior Notes.

     14. Defeasance. The Indenture contains provisions (which provisions apply
to this Series D Senior Note) for defeasance at any time of (a) the entire
indebtedness of the Company in respect of this Series D Senior Note and (b)
certain restrictive covenants and Defaults and Events of Default, in each case
upon compliance by the Company with certain conditions set forth therein.

     15. Authentication. This Series D Senior Note shall not be valid until the
Trustee signs the certificate of authentication on the other side of this Series
D Senior Note.

     16. Abbreviations. Customary abbreviations may be used in the name of a
Holder of Series D Senior Notes or an assignee, such as: TEN


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COM (= tenants in common), TENANT (= tenants by the entireties), JT TEN (= joint
tenants with right of survivorship and not as tenants in common), CUST (=
Custodian), and U/G/M/A (= Uniform Gifts to Minors Act).

     17. GOVERNING LAW. THE INDENTURE AND THIS SERIES D SENIOR NOTE SHALL BE
GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK
WITHOUT REGARD TO PRINCIPLES OF CONFLICTS OF LAW.

     The Company will furnish to any Holder of Series D Senior Notes upon
written request and without charge a copy of the Indenture. Requests
may be made to:

                 THE AES CORPORATION
                 1001 North 19th Street, Suite 2000
                 Arlington, Virginia  22209
                 Telephone:  (703) 522-1315
                 Telecopy:  (703) 528-4510

                 Attention:  General Counsel


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                                 ASSIGNMENT FORM

If you the holder want to assign this Series D Senior Note, fill in the form
below and have your signature guaranteed:

     I or we assign and transfer this Series D Senior Note to_________________
______________________________________________________________________________
(Insert assignee's social security or tax ID number)__________________________
______________________________________________________________________________
(Print or type assignee's name, address and zip code) and irrevocably appoint
agent to transfer this Series D Senior Note on the books of the Company. The
agent may substitute another to act for him.

Date:_____________________     Your signature:_______________________________
                                              (Sign exactly as your name appears
                                              on the other side of this Series D
                                              Senior Note)

Signature Guarantee:__________________________________________________________

     Signatures must be guaranteed by an "eligible guarantor institution"
meeting the requirements of the Registrar, which requirements include membership
or participation in the Securities Transfer Agents Medallion Program ("STAMP")
or such other "signature guarantee program" as may be determined by the
Registrar in addition to, or in substitution for, STAMP, all in accordance with
the Securities Exchange Act of 1934, as amended.


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