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                                                   EXHIBIT 10.20



                              June 27, 1988


Hendrik A. Verfaillie
Monsanto Company
800 North Lindbergh
St. Louis, MO 63167

Dear Hendrik:

If the Company receives any proposal from a third party
concerning a possible business combination with, or an
acquisition of the Company, the Board of Directors believes it
essential that the Company and the Board be able to rely upon
you to continue in your present position and that the Company
be able to receive your advice in assessing the proposal, in
determining what is in the best interests of the Company and
its shareholders and in determining what action the Company
should take.  Your continued employment with the Company
during the assessment of any such proposal and following any
business combination will provide critical continuity of
management and will enhance the value of the Company.

As you know, in order to be eligible for unreduced early
retirement pension benefits, you must retire from the Company
after attainment of age 55 and your age and years of service
must total 80 ("Combo 80").  Moreover, in order for you and
your eligible dependents to be eligible for retiree medical
benefits plan coverage, you must terminate employment after
age 55 with 10 or more years of benefit service.  Because you
are not yet age 55, you are not yet Combo 80 eligible, and you
and your eligible dependents are not yet eligible for retiree
medical benefits plan coverage.  Therefore, the Executive
Compensation and Development Committee ("ECDC") has decided
that in order to minimize any distraction that could be caused
by the personal uncertainties and risks created by a change of
control proposal, it is in the Company's best interests to
provide you at this time with the early retirement protection
described below.

     A.   Supplemental Pension.
          --------------------
          If you Terminate Employment with the Company after a
          Change of Control and are not yet Combo 80 eligible,
          you will be paid a Supplemental Pension in an amount
          equal to the difference between what you would have


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          received from the Monsanto Company Salaried
          Employees' Pension Plan ("Salaried Pension Plan")
          and the Monsanto Company ERISA Parity Pension Plan
          ("Parity Pension Plan") in effect when you Terminate
          Employment (computed without reduction for early
          commencement of benefits) less what you are actually
          paid from both plans.

          Your Supplemental Pension will be paid to you
          monthly under the same option election and with the
          same beneficiary designation you make under the
          Salaried Pension Plan.  In order to receive your
          Supplemental Pension in the form of monthly
          payments, you must, in the case of retirement,
          commence receiving your pension payments from the
          Salaried Pension Plan on the first day of the month
          coinciding with or following your retirement date.
          In the case of vested termination, you must commence
          receiving your pension payments on the first day of
          the month coinciding with or following your
          attainment of age 55.

          Alternatively, you may elect to receive the
          actuarially commuted value of your Supplemental
          Pension, or a portion thereof, in a single sum, in
          which case the value of your Supplemental Pension
          will be calculated actuarially by the Qualified
          Actuary for the Salaried Pension Plan who was
          serving as such immediately prior to the Change of
          Control using the actuarial assumptions applicable
          to the Plan.  The amount so calculated by the
          Qualified Actuary will be paid to you in a single
          sum as soon as practicable after you Terminate
          Employment.

          In the event that you do not elect to receive your
          Supplemental Pension in a single sum, and the amount
          payable to you under your Key Executive Employment
          Agreement is limited because of the Excise Tax
          limitation set forth in Section 3(b) of the Key
          Executive Employment Agreement, the Public
          Accounting Firm in considering how much can be paid
          to you under the Excise Tax Limitation provision of
          the Key Executive Employment Agreement will first
          reduce the cash portion of any Payment which is
          subject to Excise Taxes in order to preserve as much
          of your Supplemental Pension as possible.


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     B.   Parity Plan/Bonus Deferral Plan.
          -------------------------------
          The ECDC has amended the Pension Parity Plan to
          permit you to receive the actuarially commuted value
          of your accrued benefit under the Plan in a single
          sum when you Terminate Employment even if you are
          not eligible to receive a Commuted Value Option
          distribution from the Salaried Pension Plan.  It
          also has amended the Deferred Payment Plan ("Bonus
          Deferral Plan") to permit you to receive the amount
          of any deferred bonus plus accrued earnings thereon
          and the actuarially commuted value of any amounts
          accrued under the Supplemental Pension Plan in a
          single sum when you Terminate Employment.

     C.   Medical Coverage.
          ----------------
          If at the time you Terminate Employment you are not
          eligible for Retiree Medical Plan coverage, you will
          receive a $15,000 payment to compensate you for the
          loss of medical plan coverage for you and your
          eligible dependents.  If you wish, and do not have
          coverage through other employment, you may elect
          COBRA continuation and keep your Monsanto coverage
          in effect for up to 18 months following your
          Termination of Employment, at which time you may
          purchase a conversion policy from Metropolitan Life
          Insurance Company.  You have an absolute right to
          this $15,000 payment regardless of when you obtain
          continuation or replacement coverage and regardless
          of what such coverage costs.

     D.   Executive Life Insurance Coverage.
          ---------------------------------
          The ECDC has amended the Executive Life Insurance
          Plan to require the Company to continue to make its
          premium payments under the terms of the plan, the
          underlying policy and your collateral assignment
          agreement even if you Terminate Employment prior to
          age 62.  This provision is contingent upon you
          continuing to make your required contributions under
          the plan.

You must make your election to receive the actuarially
commuted value of your Supplemental Pension, any Pension
Parity Plan or Supplemental Pension Plan benefits and any
deferred bonus payments in a single sum by signing the


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enclosed election form and filing it with the Management
Liaison Officer to the ECDC within 30 days of the date of this
letter.  If you make this election, it will remain binding on
you unless there is a Change of Control, in which case you
will be entitled to make a second written election within 30
days of the Change of Control to receive your Supplemental
Pension as monthly payments and any Pension Parity Plan or
Supplemental Pension Plan benefits and any deferred bonus pay-
ments as otherwise permitted under the terms of these plans.
Unless you make this second written election in a timely
manner, your election to receive it in a single sum will be
binding on you and irrevocable.

As used herein, the term "Terminate Employment" has the same
meaning as does the term "Termination of Employment" in the
Key Executive Employment Agreement ("Key Executive Employment
Agreement") executed by you and the Company contemporaneously
with this Agreement.  The terms "Change of Control", "Payment"
and "Termination of Employment" have the same meanings as do
the same terms in the Key Executive Employment Agreement, a
copy of which is attached hereto as Exhibit A.  For purposes
of this Agreement, the relevant sections of the Key Executive
Employment Agreement are incorporated by reference herein and
made a part hereof.

Where appropriate, all references to "the Company" or
"Monsanto" also refer to any Monsanto subsidiary or affiliate
and to any successor corporation.  The Company's obligation to
pay you the benefits set forth herein is absolute and
unconditional and will not be affected by any circumstances,
including, without limitation, any set-off, counterclaim,
recoupment, defense or other right which the Company may have
against you.  The Company will make from any payments all tax
and other withholdings required by law to be made.  This
Agreement will inure to your benefit and that of your
beneficiary and will be binding upon the Company and any
successor of the Company.  Moreover, the benefits provided
under this Agreement are not intended to qualify under Section
401 of the Internal Revenue Code.  This Agreement will not be
subject to the claims of your creditors and may not be
assigned either by you or your spouse or any beneficiary, and
any attempted assignment, pledge or other transfer will be
void.  Finally, the Supplemental Pension will expire and
become null and void if you are still employed by the Company
when you attain Combo 80 eligibility and the payment for
medical plan coverage will expire if you become eligible for
retiree medical benefits plan coverage.


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On behalf of the Company, I am pleased to be able to extend
this Agreement you.  Please acknowledge your acceptance of its
terms by signing both copies of this letter and returning one
copy to R. L. Berra, Management Liaison Officer to the ECDC,
c/o Mr. R. N. Abercrombie, Mail Zone B2NA.

                              Very truly yours,


ACKNOWLEDGED AND AGREED:      MONSANTO COMPANY,

/s/ H.A. Verfaillie           /s/ Richard J. Mahoney
-------------------------
       (name)                 Richard J. Mahoney