

                                                                    EXHIBIT 99.4


                               OFFER TO EXCHANGE
               8 3/8% SENIOR SUBORDINATED EXCHANGE NOTES DUE 2007
                          FOR ANY AND ALL OUTSTANDING
                    8 3/8% SENIOR SUBORDINATED NOTES DUE 2007
                                       OF
                              THE AES CORPORATION

To Our Clients:

We are  enclosing  herewith a  Prospectus,  dated  August __,  1997,  of The AES
Corporation (the  "Company"),  a Delaware  corporation,  and a related Letter of
Transmittal  (which together  constitute the "Exchange  Offer")  relating to the
offer by the Company to exchange its 8 3/8% Senior  Subordinated  Exchange Notes
due 2007  (the  "New  Notes"),  pursuant  to an  offering  registered  under the
Securities Act of 1933, as amended (the "Securities  Act"), for a like principal
amount of its issued and outstanding 8 3/8% Senior  Subordinated  Notes due 2007
(the "Old Notes") upon the terms and subject to the  conditions set forth in the
Exchange Offer.

PLEASE  NOTE THAT THE OFFER  WILL  EXPIRE AT 5:00 P.M.,  NEW YORK CITY TIME,  ON
SEPTEMBER __, 1997, UNLESS EXTENDED.

The  Offer is not  conditioned  upon  any  minimum  number  of Old  Notes  being
tendered.


We are the  holder of  record  and/or  participant  in the  book-entry  transfer
facility  of Old Notes held by us for your  account.  A tender of such Old Notes
can be made only by us as the record holder and/or participant in the book-entry
transfer facility and pursuant to your  instructions.  The Letter of Transmittal
is  furnished  to you for your  information  only and  cannot  be used by you to
tender Old Notes held by us for your account.


We request  instructions  as to whether you wish to tender any or all of the Old
Notes held by us for your account  pursuant to the terms and  conditions  of the
Exchange Offer. We also request that you confirm that we may on your behalf make
the representations contained in the Letter of Transmittal.


Pursuant to the Letter of  Transmittal,  each holder of Old Notes will represent
to the Company that (i) the New Notes  acquired in the Exchange  Offer are being
obtained in the  ordinary  course of business of the person  receiving  such New
Notes, whether or not such person is such holder, (ii) neither the holder of the
Old Notes nor any such other person has an arrangement or understanding with any
person to participate in the distribution of such New Notes, (iii) if the holder
is not a broker-dealer or is a broker-dealer  but will not receive New Notes for
its own account in exchange for Old Notes, neither the holder nor any such other
person is  engaged in or intends to  participate  in a  distribution  of the New
Notes and (iv) neither the holder nor any such other person is an "affiliate" of
the Company  within the meaning of Rule 405 under the Securities Act of 1933, as
amended.  If the tendering holder is a broker-dealer  (whether or not it is also
an "affiliate")  that will receive New Notes for its own account in exchange for
Old Notes, we will represent on behalf of such  broker-dealer that the Old Notes
to  be  exchanged  for  the  New  Notes  were  acquired  by it  as a  result  of
market-making activities or other trading activities,  and acknowledge on behalf
of such broker-dealer that it will deliver a prospectus meeting the requirements
of the Act in  connection  with any resale of such New Notes.  By  acknowledging
that it will deliver and by delivering a prospectus  meeting the requirements of
the Act in connection with any resale of such New Notes,  the undersigned is not
deemed to admit that it is an "underwriter" within the meaning of the Act.



                                    Very truly yours,



                                    
