SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549



                                    FORM 8-K


                                 CURRENT REPORT




     Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934



                Date of Report (Date of earliest event reported):
                                October 10, 2003





                               AMEREN CORPORATION
             (Exact name of registrant as specified in its charter)




         Missouri                       1-14756                43-1723446
(State or other jurisdiction          (Commission           (I.R.S. Employer
     of incorporation)                File Number)          Identification No.)




                 1901 Chouteau Avenue, St. Louis, Missouri 63103
              (Address of principal executive offices and Zip Code)






       Registrant's telephone number, including area code: (314) 621-3222

<PAGE>

ITEM 5. OTHER EVENTS AND REGULATION FD DISCLOSURE.

The following  changes in directors  and officers were  announced on October 10,
2003:

Ameren Corporation
------------------

o    Susan S. Elliott,  Chairman and Chief Executive  Officer of Systems Service
     Enterprises,  Inc. (SSE), a privately held St. Louis information technology
     firm,  was  elected to fill a vacancy on the board of  directors  effective
     October 10, 2003. Ms.  Elliott,  age 66, founded SSE in 1966. She serves on
     the board of  directors of Angelica  Corporation,  the  Automobile  Club of
     Missouri, the Regional Business Council and the St. Louis Science Center.

o    Charles W. Mueller,  Chairman and Chief Executive  Officer,  will retire on
     December 31, 2003. He will continue as a member of the board of directors.

o    Gary L. Rainwater,  President and Chief Operating Officer, will succeed Mr.
     Mueller  as  Chairman  and Chief  Executive  Officer  upon his  retirement.
     Effective  January 1, 2004,  Mr.  Rainwater  will serve as Chairman,  Chief
     Executive  Officer  and  President.  Mr.  Rainwater  was  elected to fill a
     vacancy on the board of directors effective October 10, 2003.

o    Warner L. Baxter, Senior Vice President (principal financial officer),  was
     elected  Executive Vice  President and Chief  Financial  Officer  effective
     October 10, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy, General Counsel and Secretary effective October 10, 2003.

Union Electric Company (AmerenUE) (Subsidiary)
----------------------

o    Paul A.  Agathen,  director  and Senior  Vice  President  will  retire from
     AmerenUE and in  conjunction  therewith will  relinquish  his  directorship
     effective October 10, 2003.

o    Garry L. Randolph,  Senior Vice President,  was elected to fill the vacancy
     on the board of directors  created by Mr.  Agathen's  retirement  effective
     October 10, 2003.

o    Charles W. Mueller,  Chairman,  Chief Executive Officer and director,  will
     retire on December 31, 2003.

o    Gary L. Rainwater,  President,  Chief Operating Officer and director,  will
     succeed  Mr.  Mueller as  Chairman  and Chief  Executive  Officer  upon his
     retirement.  Effective  January  1,  2004,  Mr.  Rainwater  will  serve  as
     Chairman, Chief Executive Officer, President and director.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

                                       2
<PAGE>

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

Central Illinois Public Service Company (AmerenCIPS) (Subsidiary)
---------------------------------------

o    Paul A.  Agathen,  director  and Senior  Vice  President,  will retire from
     AmerenCIPS and in conjunction  therewith will  relinquish his  directorship
     effective October 10, 2003.

o    Daniel F. Cole,  Senior Vice President,  was elected to fill the vacancy on
     the  board of  directors  created  by Mr.  Agathen's  retirement  effective
     October 10, 2003.

o    Charles W. Mueller, director, will retire on December 31, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

CILCORP Inc. (Subsidiary)
------------

o    Paul A.  Agathen,  director  and Senior  Vice  President,  will retire from
     CILCORP Inc. and in conjunction  therewith will relinquish his directorship
     effective October 10, 2003.

o    Daniel F. Cole,  Senior Vice President,  was elected to fill the vacancy on
     the  board of  directors  created  by Mr.  Agathen's  retirement  effective
     October 10, 2003.

o    Charles W.  Mueller,  Chairman  and  director,  will retire on December 31,
     2003.

o    Gary L. Rainwater,  President,  Chief Executive Officer and director,  will
     succeed Mr. Mueller as Chairman upon his retirement.  Effective  January 1,
     2004,  Mr.  Rainwater  will serve as  Chairman,  Chief  Executive  Officer,
     President and director.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

                                       3

<PAGE>


Central Illinois Light Company (AmerenCILCO) (Subsidiary)
------------------------------

o    Paul A.  Agathen,  director  and Senior  Vice  President,  will retire from
     AmerenCILCO and in conjunction  therewith will relinquish his  directorship
     effective October 10, 2003.

o    Daniel F. Cole,  Senior Vice President,  was elected to fill the vacancy on
     the  board of  directors  created  by Mr.  Agathen's  retirement  effective
     October 10, 2003.

o    Charles W.  Mueller,  Chairman  and  director,  will retire on December 31,
     2003.

o    Gary L. Rainwater,  President,  Chief Executive Officer and director,  will
     succeed Mr. Mueller as Chairman upon his retirement.  Effective  January 1,
     2004,  Mr.  Rainwater  will serve as  Chairman,  Chief  Executive  Officer,
     President and director.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

Ameren Energy Generating Company (Subsidiary)
--------------------------------

o    Thomas R. Voss,  Senior Vice  President,  was elected  President  effective
     October 10, 2003 replacing Daniel F. Cole.

o    Paul A.  Agathen,  director  and Senior  Vice  President,  will retire from
     Ameren  Energy  Generating  Company  and  in  conjunction   therewith  will
     relinquish his directorship effective October 10, 2003.

o    Thomas R. Voss was  elected to fill the  vacancy on the board of  directors
     created by Mr. Agathen's retirement effective October 10, 2003.

o    Charles W. Mueller, director, will retire on December 31, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

                                       4

<PAGE>


Ameren Services Company
-----------------------

o    Paul A. Agathen, director and Senior Vice President will retire from Ameren
     Services   Company  and  in  conjunction   therewith  will  relinquish  his
     directorship effective October 10, 2003.

o    Daniel F. Cole,  Senior Vice President,  was elected to fill the vacancy on
     the  board of  directors  created  by Mr.  Agathen's  retirement  effective
     October 10, 2003.

o    Charles W. Mueller,  Chairman,  Chief Executive Officer and director,  will
     retire on December 31, 2003.

o    Gary L. Rainwater,  President,  Chief Operating Officer and director,  will
     succeed  Mr.  Mueller as  Chairman  and Chief  Executive  Officer  upon his
     retirement.  Effective  January  1,  2004,  Mr.  Rainwater  will  serve  as
     Chairman, Chief Executive Officer, President and director.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

AmerenEnergy, Inc. (Subsidiary)
------------------

o    Thomas R. Voss was elected  President  effective October 10, 2003 replacing
     Daniel F. Cole.

o    Paul  A.  Agathen,  director,  in  conjunction  with  his  retirement  will
     relinquish his directorship effective October 10, 2003.

o    Thomas R. Voss was  elected to fill the  vacancy on the board of  directors
     created by Mr. Agathen's retirement effective October 10, 2003.

o    Charles W. Mueller, director, will retire on December 31, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

AmerenEnergy Resources Company (Subsidiary)
------------------------------

o    Thomas R. Voss was elected  President  effective October 10, 2003 replacing
     Daniel F. Cole.

                                       5

<PAGE>

o    Paul  A.  Agathen,  director,  in  conjunction  with  his  retirement  will
     relinquish his directorship effective October 10, 2003.

o    Thomas R. Voss was  elected to fill the  vacancy on the board of  directors
     created by Mr. Agathen's retirement effective October 10, 2003.

o    Charles W. Mueller, director, will retire on December 31, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

Ameren Energy Fuels and Services Company (Subsidiary)
----------------------------------------

o    Thomas R. Voss was elected  President  effective October 10, 2003 replacing
     Daniel F. Cole.

o    Paul  A.  Agathen,  director,  in  conjunction  with  his  retirement  will
     relinquish his directorship effective October 10, 2003.

o    Thomas R. Voss was  elected to fill the  vacancy on the board of  directors
     created by Mr. Agathen's retirement effective October 10, 2003.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy, General Counsel and Secretary effective October 10, 2003.

Ameren Energy Marketing Company (Subsidiary)
-------------------------------

o    Thomas R. Voss was elected  President  effective October 10, 2003 replacing
     Daniel F. Cole.

o    Paul  A.  Agathen,  director,  in  conjunction  with  his  retirement  will
     relinquish his directorship effective October 10, 2003.

o    Thomas R. Voss was  elected to fill the  vacancy on the board of  directors
     created by Mr. Agathen's retirement effective October 10, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy, General Counsel and Secretary effective October 10, 2003.

                                       6

<PAGE>


AmerenEnergy Resources Generating Company (Subsidiary)
-----------------------------------------

o    Thomas R. Voss,  Senior Vice  President,  was elected  President  effective
     October 10, 2003 replacing Daniel F. Cole.

o    Paul  A.  Agathen,  director,  in  conjunction  with  his  retirement  will
     relinquish his directorship effective October 10, 2003.

o    Thomas R. Voss was  elected to fill the  vacancy on the board of  directors
     created by Mr. Agathen's retirement effective October 10, 2003.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy, General Counsel and Secretary effective October 10, 2003.



                                    SIGNATURE

     Pursuant to the  requirements  of the Securities  Exchange Act of 1934, the
Registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned thereunto duly authorized.

                                          AMEREN CORPORATION
                                           (Registrant)


                                          By       /s/ Martin J. Lyons
                                             -------------------------------
                                          Name:        Martin J. Lyons
                                          Title: Vice President and Controller
                                                 (Principal Accounting Officer)

Date:  October 10, 2003


                                       7
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SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

                                    FORM 8-K

                                 CURRENT REPORT

     Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

                Date of Report (Date of earliest event reported):
                                October 10, 2003

                               AMEREN CORPORATION
             (Exact name of registrant as specified in its charter)

         Missouri                       1-14756                43-1723446
(State or other jurisdiction          (Commission           (I.R.S. Employer
     of incorporation)                File Number)          Identification No.)

                 1901 Chouteau Avenue, St. Louis, Missouri 63103
              (Address of principal executive offices and Zip Code)

       Registrant's telephone number, including area code: (314) 621-3222
ITEM 5. OTHER EVENTS AND REGULATION FD DISCLOSURE.

The following  changes in directors  and officers were  announced on October 10,
2003:

Ameren Corporation
------------------

o    Susan S. Elliott,  Chairman and Chief Executive  Officer of Systems Service
     Enterprises,  Inc. (SSE), a privately held St. Louis information technology
     firm,  was  elected to fill a vacancy on the board of  directors  effective
     October 10, 2003. Ms.  Elliott,  age 66, founded SSE in 1966. She serves on
     the board of  directors of Angelica  Corporation,  the  Automobile  Club of
     Missouri, the Regional Business Council and the St. Louis Science Center.

o    Charles W. Mueller,  Chairman and Chief Executive  Officer,  will retire on
     December 31, 2003. He will continue as a member of the board of directors.

o    Gary L. Rainwater,  President and Chief Operating Officer, will succeed Mr.
     Mueller  as  Chairman  and Chief  Executive  Officer  upon his  retirement.
     Effective  January 1, 2004,  Mr.  Rainwater  will serve as Chairman,  Chief
     Executive  Officer  and  President.  Mr.  Rainwater  was  elected to fill a
     vacancy on the board of directors effective October 10, 2003.

o    Warner L. Baxter, Senior Vice President (principal financial officer),  was
     elected  Executive Vice  President and Chief  Financial  Officer  effective
     October 10, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy, General Counsel and Secretary effective October 10, 2003.

Union Electric Company (AmerenUE) (Subsidiary)
----------------------

o    Paul A.  Agathen,  director  and Senior  Vice  President  will  retire from
     AmerenUE and in  conjunction  therewith will  relinquish  his  directorship
     effective October 10, 2003.

o    Garry L. Randolph,  Senior Vice President,  was elected to fill the vacancy
     on the board of directors  created by Mr.  Agathen's  retirement  effective
     October 10, 2003.

o    Charles W. Mueller,  Chairman,  Chief Executive Officer and director,  will
     retire on December 31, 2003.

o    Gary L. Rainwater,  President,  Chief Operating Officer and director,  will
     succeed  Mr.  Mueller as  Chairman  and Chief  Executive  Officer  upon his
     retirement.  Effective  January  1,  2004,  Mr.  Rainwater  will  serve  as
     Chairman, Chief Executive Officer, President and director.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

                                       2
o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

Central Illinois Public Service Company (AmerenCIPS) (Subsidiary)
---------------------------------------

o    Paul A.  Agathen,  director  and Senior  Vice  President,  will retire from
     AmerenCIPS and in conjunction  therewith will  relinquish his  directorship
     effective October 10, 2003.

o    Daniel F. Cole,  Senior Vice President,  was elected to fill the vacancy on
     the  board of  directors  created  by Mr.  Agathen's  retirement  effective
     October 10, 2003.

o    Charles W. Mueller, director, will retire on December 31, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

CILCORP Inc. (Subsidiary)
------------

o    Paul A.  Agathen,  director  and Senior  Vice  President,  will retire from
     CILCORP Inc. and in conjunction  therewith will relinquish his directorship
     effective October 10, 2003.

o    Daniel F. Cole,  Senior Vice President,  was elected to fill the vacancy on
     the  board of  directors  created  by Mr.  Agathen's  retirement  effective
     October 10, 2003.

o    Charles W.  Mueller,  Chairman  and  director,  will retire on December 31,
     2003.

o    Gary L. Rainwater,  President,  Chief Executive Officer and director,  will
     succeed Mr. Mueller as Chairman upon his retirement.  Effective  January 1,
     2004,  Mr.  Rainwater  will serve as  Chairman,  Chief  Executive  Officer,
     President and director.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

                                       3
Central Illinois Light Company (AmerenCILCO) (Subsidiary)
------------------------------

o    Paul A.  Agathen,  director  and Senior  Vice  President,  will retire from
     AmerenCILCO and in conjunction  therewith will relinquish his  directorship
     effective October 10, 2003.

o    Daniel F. Cole,  Senior Vice President,  was elected to fill the vacancy on
     the  board of  directors  created  by Mr.  Agathen's  retirement  effective
     October 10, 2003.

o    Charles W.  Mueller,  Chairman  and  director,  will retire on December 31,
     2003.

o    Gary L. Rainwater,  President,  Chief Executive Officer and director,  will
     succeed Mr. Mueller as Chairman upon his retirement.  Effective  January 1,
     2004,  Mr.  Rainwater  will serve as  Chairman,  Chief  Executive  Officer,
     President and director.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

Ameren Energy Generating Company (Subsidiary)
--------------------------------

o    Thomas R. Voss,  Senior Vice  President,  was elected  President  effective
     October 10, 2003 replacing Daniel F. Cole.

o    Paul A.  Agathen,  director  and Senior  Vice  President,  will retire from
     Ameren  Energy  Generating  Company  and  in  conjunction   therewith  will
     relinquish his directorship effective October 10, 2003.

o    Thomas R. Voss was  elected to fill the  vacancy on the board of  directors
     created by Mr. Agathen's retirement effective October 10, 2003.

o    Charles W. Mueller, director, will retire on December 31, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

                                       4
Ameren Services Company
-----------------------

o    Paul A. Agathen, director and Senior Vice President will retire from Ameren
     Services   Company  and  in  conjunction   therewith  will  relinquish  his
     directorship effective October 10, 2003.

o    Daniel F. Cole,  Senior Vice President,  was elected to fill the vacancy on
     the  board of  directors  created  by Mr.  Agathen's  retirement  effective
     October 10, 2003.

o    Charles W. Mueller,  Chairman,  Chief Executive Officer and director,  will
     retire on December 31, 2003.

o    Gary L. Rainwater,  President,  Chief Operating Officer and director,  will
     succeed  Mr.  Mueller as  Chairman  and Chief  Executive  Officer  upon his
     retirement.  Effective  January  1,  2004,  Mr.  Rainwater  will  serve  as
     Chairman, Chief Executive Officer, President and director.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

AmerenEnergy, Inc. (Subsidiary)
------------------

o    Thomas R. Voss was elected  President  effective October 10, 2003 replacing
     Daniel F. Cole.

o    Paul  A.  Agathen,  director,  in  conjunction  with  his  retirement  will
     relinquish his directorship effective October 10, 2003.

o    Thomas R. Voss was  elected to fill the  vacancy on the board of  directors
     created by Mr. Agathen's retirement effective October 10, 2003.

o    Charles W. Mueller, director, will retire on December 31, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

AmerenEnergy Resources Company (Subsidiary)
------------------------------

o    Thomas R. Voss was elected  President  effective October 10, 2003 replacing
     Daniel F. Cole.

                                       5
o    Paul  A.  Agathen,  director,  in  conjunction  with  his  retirement  will
     relinquish his directorship effective October 10, 2003.

o    Thomas R. Voss was  elected to fill the  vacancy on the board of  directors
     created by Mr. Agathen's retirement effective October 10, 2003.

o    Charles W. Mueller, director, will retire on December 31, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy,  General  Counsel and  Secretary  effective  October 10, 2003.  Mr.
     Sullivan was elected to fill the vacancy on the board of directors  created
     by Mr. Mueller's retirement effective January 1, 2004.

Ameren Energy Fuels and Services Company (Subsidiary)
----------------------------------------

o    Thomas R. Voss was elected  President  effective October 10, 2003 replacing
     Daniel F. Cole.

o    Paul  A.  Agathen,  director,  in  conjunction  with  his  retirement  will
     relinquish his directorship effective October 10, 2003.

o    Thomas R. Voss was  elected to fill the  vacancy on the board of  directors
     created by Mr. Agathen's retirement effective October 10, 2003.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy, General Counsel and Secretary effective October 10, 2003.

Ameren Energy Marketing Company (Subsidiary)
-------------------------------

o    Thomas R. Voss was elected  President  effective October 10, 2003 replacing
     Daniel F. Cole.

o    Paul  A.  Agathen,  director,  in  conjunction  with  his  retirement  will
     relinquish his directorship effective October 10, 2003.

o    Thomas R. Voss was  elected to fill the  vacancy on the board of  directors
     created by Mr. Agathen's retirement effective October 10, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy, General Counsel and Secretary effective October 10, 2003.

                                       6
AmerenEnergy Resources Generating Company (Subsidiary)
-----------------------------------------

o    Thomas R. Voss,  Senior Vice  President,  was elected  President  effective
     October 10, 2003 replacing Daniel F. Cole.

o    Paul  A.  Agathen,  director,  in  conjunction  with  his  retirement  will
     relinquish his directorship effective October 10, 2003.

o    Thomas R. Voss was  elected to fill the  vacancy on the board of  directors
     created by Mr. Agathen's retirement effective October 10, 2003.

o    Warner L. Baxter,  Senior Vice President  (principal financial officer) and
     director,  was elected Executive Vice President and Chief Financial Officer
     effective October 10, 2003.

o    Steven R. Sullivan,  Vice President Regulatory Policy,  General Counsel and
     Secretary,  was  elected  Senior  Vice  President   Governmental/Regulatory
     Policy, General Counsel and Secretary effective October 10, 2003.

                                    SIGNATURE

     Pursuant to the  requirements  of the Securities  Exchange Act of 1934, the
Registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned thereunto duly authorized.

                                          AMEREN CORPORATION
                                           (Registrant)

                                          By       /s/ Martin J. Lyons
                                             -------------------------------
                                          Name:        Martin J. Lyons
                                          Title: Vice President and Controller
                                                 (Principal Accounting Officer)

Date:  October 10, 2003

                                       7