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                                                                   EXHIBIT 10.20


March 5, 2002


Mr. Peter A. Espinosa
9123 W. 145th Place
Overland Park, KS  66221
US

Dear Pete:

On behalf of Retek Inc., we are pleased to offer you the position of Sr. Vice
President, Worldwide Field Operations in our Worldwide Sales business unit as
follows:

o    You will report to me (Steve Ladwig, President and CEO).

o    Your salary will initially be $23,333.33 (US) per month.

o    You are eligible to participate in our business unit incentive program.
     Your targeted annual incentive will be $270,000 annually, prorated based on
     the number of months employed in the calendar year. Incentive pay is based
     on a combination of corporate and individual performance, payable
     quarterly.

o    We will pay you a signing bonus of $100,000.00, less applicable
     withholdings (the "Signing Bonus"), with your first month's salary.

     In exchange for the signing bonus you agree that:

     1.   If you resign your employment with Retek within the first twelve (12)
          months, you will repay 100% of the Signing Bonus.

     2.   You will repay any amount due from you under this Agreement within 30
          days after your departure from Retek.

o    Upon submission of valid moving expense receipts, Retek will also reimburse
     you for reasonable and customary relocation expenses per the information
     you received, under separate cover, from Dick Lueck outlining your specific
     relocation terms

     1.   If you resign your employment with Retek within the first twelve (12)
          months, you will repay 100% of the relocation expense.

     2.   You will repay any amount due from you under this Agreement within 30
          days after your departure from Retek.

o    Any commuting expenses incurred prior to your relocation from Overland
     Park, Kansas will be considered normal business travel expense.

o    We would like to announce your acceptance to our Board of Directors at our
     next meeting on March 14, 2002. Public announcement will be at a future
     date mutually agreed upon.



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Mr. Peter A. Espinosa
February 27, 2002
Page 2 of 4


o    We will recommend to Retek's Board of Directors that you be granted an
     option to purchase 250,000 shares of Retek Common Stock at the current fair
     market value, which will be the closing NASDAQ price on your date of hire.

o    Retek will initiate a change of control agreement for you within the first
     six (6) months of your employment.

You will be eligible to participate in the employee benefits program established
by Retek for its employees. These benefits generally include health, vision,
prescription drug, dental, life, short- and long-term disability and paid
vacation. In addition, you may choose to enroll in our voluntary 401(k) plan and
you may participate in our Employee Stock Purchase Plan, subject to the terms of
those plans.

This offer is contingent upon verification of the information you provided on
your employment application. Retek may rescind this offer should discrepancies
be discovered.

Your employment with Retek, should you accept this offer, will not be for any
specific term and may be terminated at any time, with or without cause and with
or without notice, by you or by the company for any reason. Any contrary
representations or agreements, which may have been made to you, are superseded
by this offer. The at-will nature of your employment described in this offer
letter shall constitute the entire agreement between you and Retek concerning
the duration of your employment and the circumstances under which either you or
the company may terminate the agreement that changes the at-will status of
employment with Retek. The at-will term of your employment with Retek can only
be changed in a written document signed by you and the president of Retek, which
expressly states the intention to modify the at-will term of your employment
agreement.

If your employment is terminated within the first year, and upon your execution
at the time of your termination of a release agreement by which you agree to
release all claims you have or may claim to have at that time against Retek or
any of its subsidiaries, affiliates or employees, you will receive severance in
the form of six (6) months of your base salary in effect at the time of your
termination, only if your employment is terminated for a reason other than:

           (1)      misconduct by you;

           (2)      neglect of any job duties assigned to you; or

           (3)      breach by you of any of the agreements you have signed with
                    Retek or your violation of any of Retek's policies.

If your employment is terminated for any of these stated reasons, Retek shall
owe you none of the severance referenced above. Retek's agreement to provide you
with the severance shall not alter or change the at-will nature of your
employment. Nor shall it provide you with any right to receive any additional
sums from Retek in any form or any additional options beyond those specifically
awarded to you as part of this offer letter.

By signing the offer below, you acknowledge and agree that length of employment,
promotions, positive performance reviews, pay increases, bonuses, increases in
job duties or responsibilities and other changes during employment will not
change the at-will term of your employment with Retek and will not create any
implied contract.

As an employee of Retek, you will be required to comply with all Company
policies and procedures. In particular, you will be required to familiarize
yourself with and to comply with Retek's policy prohibiting unlawful harassment
and discrimination. Violation of this policy may lead to immediate termination
of employment. By signing the Invention Assignment and Confidentiality
Agreement, you are agreeing to hold in confidence any proprietary information
received as an employee of Retek and to assign to Retek any

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Mr. Peter A. Espinosa
February 27, 2002
Page 3 of 4

inventions that you may make while employed by Retek. We wish to impress upon
you that you are not to bring with you any confidential or proprietary material
of any former employer or to violate any other obligation to your former
employers.

Pete, we sincerely appreciate your interest in Retek and hope you will accept
our offer. We are tentatively preparing facilities and equipment for you based
on your date of hire.

On your date of hire, please come to 950 Nicollet Mall, Minneapolis, MN 4th
floor reception area by 8:30 A.M. and let the receptionist know you are here for
the new employee orientation. For details on how your first day will go, see the
enclosed "New Employee Orientation Agenda" schedule for your information. Also
upon your hire and start date, you will be required to provide the Company with
the legally required proof of your identity and authorization to work in the
United States. Please bring appropriate documentation with you on your date of
hire. If you are unsure of what constitutes appropriate documentation, please
review the enclosed Federal I-9 form and come prepared

IF YOU WISH TO ACCEPT THIS OFFER, PLEASE SIGN AND DATE THIS LETTER AND RETURN
ALL PAGES OF THE OFFER LETTER TO OUR VALERIE RAATZ, HUMAN RESOURCES, IN THE
ENCLOSED ENVELOPE BY MARCH 11, 2002. Please keep one copy of this letter for
your records. Contact Dick Lueck directly of your intended start date if other
than April 2, 2002.

Pete, we are excited to have you join our Retek team and I look forward to your
favorable response.

Sincerely,


/s/ Steven Ladwig

Steven Ladwig
President and CEO

Enclosures


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Mr. Peter A. Espinosa
February 27, 2002
Page 4 of 4


I agree that any dispute or claim, whether based on contract, tort, or
otherwise, relating to or arising out of my employment with the company, shall
be subject to final and binding arbitration. The arbitrator shall have
jurisdiction to determine any such claim, and may grant any relief authorized by
law. Any claim or dispute subject to arbitration shall be deemed waived, and
shall be forever barred, if arbitration is not initiated within six months of
the date the claim or dispute first arose. Any arbitration will be commenced
subject to Minnesota Statutes Chapter 572. As the Company is also engaged in
interstate commerce, this agreement is also subject to the Federal Arbitration
Act, 9 US Code, Sections 1-4.

I have read and accept this employment offer.



I expect to commence employment on
                                   --------------------------------------------

By: /s/ Peter Espinosa
    --------------------------------                     ----------------------
    Employee Signature                                   Date


Candidate Checklist - Pete, please sign and date and return all the following
documents in the enclosed prepaid envelope:

[ ]      Offer Letter;

[ ]      Invention Assignment, Non-Competition & Confidentiality Agreement;

[ ]      Arbitration Agreement and;

[ ]      Code of Ethics Policy;

[ ]      Appendix A - Acknowledgment. (Insider Trading Policy - please just
         return the Appendix A page).

[ ]      Retek Inc. Position on Drug and Alcohol Use

[ ]      Relocation Agreement

If you would like copies of your offer letter and the
agreements/acknowledgement, please make them before you return them.


For your convenience we have also enclosed the following forms for you to
complete prior to your first day at Retek. Please remember to bring them with
you on April 2nd:

[ ]      Form I-9

[ ]      Form W-4 (2002) and;

[ ]      Employee Contact Information.