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                                                                   EXHIBIT 10.20

                               September 11, 1997




Mr. Michael J. Poulos
2121 Kirby, #73
Houston, Texas  77019

Dear Mr. Poulos:

         As you know, American General Corporation ("AGC"), Western National
Corporation ("Western"), and a subsidiary of AGC have, as of the date hereof,
entered into an Agreement and Plan of Merger (the "Merger Agreement") pursuant
to which AGC will indirectly acquire all or substantially all of the stock of
Western through a merger (the "Merger").  AGC understands that you intend to
resign as Chairman of the Board, President and Chief Executive Officer of
Western upon the consummation of the Merger.  It is an important element of
AGC's decision to acquire Western through such Merger that an understanding and
agreement exist with respect to the benefits that you will receive upon such
resignation pursuant to (a) the Employment Agreement dated September 9, 1993,
between you and Conseco, Inc. and assumed by Western, as the same has been
amended from time to time (the "Employment Agreement") and (b) any and all
agreements between you and Western evidencing awards you have received from
time to time under Western's 1993 Stock and Incentive Plan (collectively, the
"Award Agreements").

         Upon the consummation of the Merger, it is our understanding that you
will resign as Chairman of the Board, President and Chief Executive Officer of
Western, effective as of the Effective Time (as such term is defined in the
Merger Agreement).  AGC agrees that it will cause Western to treat such
resignation as a "Control Termination" for purposes of the Employment Agreement
and the Award Agreements in exchange for your consent and agreement to the
following modifications and amendments to the Employment Agreement and the
Award Agreements:

o        No severance payments or other compensation or benefits will be
         provided to you pursuant to Sections 10, 11, 12, and 13 of the
         Employment Agreement following your resignation, and, in lieu thereof,
         within 10 days following your resignation, you will receive a lump sum
         cash payment in an amount equal to the sum of the amounts determined
         in accordance with the following clauses (a) and (b):

                          (a)     an amount equivalent to salary payments for
                 36 calendar months at the rate of Base Salary (as such term is
                 defined in the Employment Agreement) in effect immediately
                 prior to your resignation; and

                          (b)     an amount equivalent to 36 calendar months of
                 bonus at the greater of (1) the monthly rate of the bonus
                 payment for the bonus period that ended immediately prior to
                 your resignation date or (2) the monthly rate of the estimated
                 amount of the bonus you would have received for the bonus
                 period which includes your resignation date.
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Mr. Michael J. Poulos
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September 11, 1997


         The amount of such lump sum payment will be adjusted as provided in
         the following paragraph.

o        Although you will continue to be entitled to receive the parachute
         payment protections and benefits set forth in that certain Amendment
         to Employment Agreement dated May 14, 1997, between you and Western,
         you agree that the lump sum payment described in the preceding
         paragraph will be reduced by approximately $150,000 so that none of
         the payments and benefits provided to you in connection with the
         Merger will be nondeductible or subject you to an excise tax pursuant
         to the golden parachute payment provisions of Section 280G or Section
         4999 of the Internal Revenue Code of 1986, as amended, (the "Parachute
         Sanctions").  The $150,000 figure set forth in the preceding sentence
         is an initial estimate of the amount of the reduction necessary to
         prevent the application of the Parachute Sanctions.  However, it is
         our understanding that the lump sum payment described in the preceding
         paragraph may be reduced by a greater amount if both you and AGC agree
         that a greater reduction is necessary to prevent the application of
         the Parachute Sanctions.  The amount of any such greater reduction in
         your lump sum payment will be agreed to by you and AGC prior to the
         Merger.  After the Merger, neither Western nor AGC will have the right
         to (a) reduce your lump sum payment by any amount in excess of the
         reduction amount agreed to prior to the Merger or (b) receive a refund
         or reimbursement of any portion of your lump sum payment based upon a
         claim that such refund or reimbursement is necessary to prevent the
         application of the Parachute Sanctions.

o        Your options to purchase shares of Western common stock under
         Western's 1993 Stock and Incentive Plan will be converted into options
         to purchase shares of AGC common stock pursuant to Section 6.10(a) of
         the Merger Agreement.  Upon your resignation from Western as of the
         Effective Time, such stock options will continue to be exercisable for
         the remainder of their original 10-year term.

o        You will not be permitted to surrender to Western pursuant to the
         provisions of Section 14 of the Employment Agreement (or any similar
         provision in an Award Agreement) any of your options to acquire
         Western common stock or shares of Western common stock that you own.
         However, in lieu of such right, you may elect, within 60 days after
         your resignation date, to receive a lump sum cash payment in return
         for your surrender of (a) all or any portion of the AGC stock options
         then outstanding and received by you in accordance with the terms of
         the Merger Agreement in exchange for your Western stock options (the
         "Unexercised Exchange Options") and (b) all or any portion of the AGC
         common stock then owned by you and received in accordance with the
         terms of the Merger Agreement in exchange for your shares of Western
         common stock (the "Owned Exchange Stock").  For each Unexercised
         Exchange Option to purchase one share of AGC common stock that you
         elect to surrender as provided above, you will receive an amount equal
         to the difference, if any, between (1) the New York Stock Exchange
         closing sales price of one share of AGC common stock on the date of
         your election (or on the next preceding trading day if your election
         is made on a non-trading day) and (2) the exercise price for such
         share of AGC common stock pursuant to the terms of the
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Mr. Michael J. Poulos
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September 11, 1997


         Unexercised Exchange Option.  For each share of Owned Exchange Stock
         that you elect to surrender as provided above, you will receive  an
         amount equal to the New York Stock Exchange closing sales price of one
         share of AGC common stock on the date of your election (or on the next
         preceding trading day if your election is made on a non-trading day).
         Any payment required pursuant to this paragraph will be paid within 10
         days after the date of your election hereunder, against execution and
         delivery by you to AGC of an appropriate agreement confirming your
         surrender of the Unexercised Exchange Options and the certificates
         duly endorsed by you for the Owned Exchange Stock.

         Notwithstanding any provision in this letter agreement to the
contrary, if the Merger Agreement is terminated without consummation of the
Merger, then this letter agreement will be of no further force and effect and
will be void ab initio.  Western shall be a third party beneficiary of our
understandings and agreements set forth in this letter agreement, and will join
in the execution of this letter agreement to evidence its agreement to be bound
by such understandings and agreements.

         If this letter agreement accurately sets forth our understandings and
agreements with respect to the subject matter hereof, please execute this
letter agreement in the space provided below.

                                       Very truly yours,

                                       AMERICAN GENERAL CORPORATION


                                       By: /s/ JON P. NEWTON                  
                                          ------------------------------------
                                          Name:  Jon P. Newton                
                                               -------------------------------
                                          Title: Vice Chairman                
                                                ------------------------------

AGREED AND ACCEPTED

this  23rd  day of September, 1997

/s/ MICHAEL J. POULOS                  
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Michael J. Poulos

         Western National Corporation joins in the execution of this letter
agreement to evidence its agreement to be bound by the understandings and
agreements set forth herein.

                                       WESTERN NATIONAL CORPORATION


                                       By: /s/ RICHARD W. SCOTT               
                                          ------------------------------------
                                          Name:  Richard W. Scott             
                                               -------------------------------
                                         Title: Vice Chairman & Chief 
                                                Investment Officer
                                                ------------------------------
                                          Date:  September  23 , 1997
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