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                                                                   EXHIBIT 10.13

[CALLIDUS SOFTWARE LETTERHEAD]

May 10, 2003

Mr. Bertram W. Rankin
340 Arboleda Drive
Los Altos, California 94024

Dear Bert:

I am pleased to offer you the position of Senior Vice President Worldwide
Marketing reporting to me effective on or before June 2, 2003.

Your target compensation as Vice President Worldwide Marketing shall be $270,000
per year. For the year ending December 31, 2003 your compensation as Vice
President Worldwide Marketing shall be pro-rated to reflect your start date.
Your 2003 compensation plan shall consist of a base salary of $16,667 per month,
a quarterly bonus of up to $10,000, calculated against specific departmental
objectives and effective for the quarters ending September 30, 2003 and December
31, 2003, and an annual bonus of $15,000 based on the terms and conditions of
the 2003 Executive Bonus Plan as stipulated by the Compensation Committee of the
Callidus Board of Directors. In order to be eligible for the executive bonus the
company must achieve at least 80% of the board approved FY/03 year end cash plan
or EBITDA plan. The bonus calculation shall be a pro-rata calculation using
either the percentage of achievement of the year end cash plan or EBITDA plan,
whichever is higher. The calculation of the bonus shall be as follows:

Annual Pro-rated Financial Bonus = ($15,000) (%* Cash Flow) or (%*EBITDA)
whichever is higher. This bonus shall be capped at 125% of the target payout
($18,750).

For the quarter ending September 30, 2003 Callidus Software will guarantee your
quarterly bonus.

In lieu of your position Callidus agrees to extend to you six months of
severance pay equal to your base salary plus benefits in the event you are
terminated for reasons other than cause.

As a further incentive I will recommend to the Board of Directors that you be
granted an option to purchase 300,000 shares of Callidus Software, Inc. common
stock subject to the vesting schedule and terms and conditions of the Company's
stock plan. In the event the company is acquired the Company will agree to
forward vest 50% of your outstanding options granted to you at that time.

The Company is an "at will" employer, which means that the employment
relationship may be terminated at any time by either the Company or by you, with
or without notice and with or without cause. By signing below, you acknowledge
that your employment at Callidus is for an unspecified duration, and neither
this letter, nor your acceptance thereof, constitutes a contract of employment.

In accordance with Callidus' standard policy, this offer is contingent upon your
completing and executing an Employment, Confidential Information and Invention
Assignment Agreement ("Invention Agreement") and upon your providing the Company
with the legally required proof of your identity. The Company also requires
proof of eligibility to work in the United States.
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Bert, on behalf of myself, the management team and the board of directors of
Callidus Software we very much look forward to your acceptance of this offer. I
have enclosed two executed copies of this offer letter. As evidence of your
acceptance, please sign both copies and return one original to me no later than
Tuesday May 13, 2003.

Sincerely,

/s/Reed D. Taussig
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Reed D. Taussig
President and CEO

Agreed and Accepted: /s/ Bert Rankin                  Date: 5/11/03
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