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                                                                    Exhibit 10.1

                                                              Unica Corporation
                                                          Reservoir Place North
                                                                170 Tracer Lane
                                                              Waltham, MA 02451
                                                             T: +1.781.839.8000
[LOGO]                                                       F: +1.781.890.0012

February 1, 2006

Mr. Ralph Goldwasser
93 Hyde Avenue
Newton Center, MA  02458

Dear Ralph:

      I am pleased to confirm our offer for you to join Unica Corporation as
Senior Vice President, and Chief Financial Officer, reporting to me in our
Waltham office, contingent upon your acceptance of the terms of our standard
Non-Competition, Non-Disclosure and Developments Agreement, a copy of which is
attached. In this role, you will be responsible for all duties and
responsibilities generally associated with being the company's financial officer
and leader of the General Administrative team.

      Your base salary will be paid at an initial rate of $10,000 per
semi-monthly pay period, which is equivalent to an annual salary of $240,000 per
year. As a regular employee, you will be eligible to participate in Unica's
standard benefit programs, which currently include paid holidays, paid vacation
(fifteen days during the first year), long term employment sabbatical program,
medical and dental coverage, life insurance, 401(k), and short/long term
disability insurance.

      You will also be eligible to receive incentive compensation designed to
reward you for your contributions to the Company's growth, revenues, and
profitability subject to Unica's Executive Bonus Plan for FY2006 (October 1,
2005-September 30, 2006). Your Bonus target for fiscal 2006 is $100,000,
prorated for this year based on your start date. This Bonus will be based on a
combination of the Company's achievement of its financial goals and the
successful achievement of your individual objectives.

      In addition, subject to the approval of the Company's Board of Directors,
you will be granted the option to purchase 100,000 shares of the Company's
common stock priced at fair market value on the grant date. The option will be
subject to the terms and conditions of the Company's 2005 Stock Incentive Plan
(the "Plan"), which includes provisions for accelerated vesting upon certain
change in control events as well as termination for Good Reason within one year
of the change in control, and will otherwise vest over a four year period on a
quarterly basis beginning one year from your start date (e.g. 25% of the options
granted will vest on the first year anniversary of your start date and the
remaining options will vest quarterly on a straight-line basis over the
remaining 3 years.) In addition, contingent upon Board of Directors approval,
you will also be granted 50,000 Restricted Stock Units, subject to the terms and
conditions of the Company's Plan, which includes provisions for accelerated
vesting upon certain change

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of control events as well as termination for Good Reason within one year of the
change in control, and will otherwise be earned ratably over a four year period.
Beginning one year from your start date, in the event of a change of control and
termination for Good Reason, all as defined in the Plan, within one year of the
change in control, all of your stock options outstanding and unvested will
become immediately exercisable, and all of the restricted stock units granted
but not vested will immediately vest. Good Reason in your stock option and
restricted stock units agreements will be defined to include failure of the
surviving entity to employ you in a position with responsibilities commensurate
with your responsibilities as Chief Financial Officer at Unica. More details of
these plans will be shared with you after you begin your employment.

      The company does not have a formal severance policy in case of termination
of employment. In the event that your employment is terminated by the company,
your severance arrangements will be consistent with company practice for senior
executives.

      The Company requires your ongoing commitment to fulfill any obligations of
confidentiality you may have with respect to trade secrets and confidential
information of former employers and any other third parties, in connection with
your performance of services for Unica. In addition, the Company requires you to
verify that the performance of your position at Unica does not and will not
breach any agreement entered into by you prior to employment with the Company
(i.e., you have not entered into any agreements with previous employers that are
in conflict with your obligations to Unica). Please provide us with a copy of
any such agreements, if they exist.

      For purposes of completing the I-9 form, please bring sufficient
documentation to demonstrate your eligibility to work in the United States on
your first day of employment.

      Ralph, I am very excited about the prospect of having you join Unica as
its Senior Vice President, Chief Financial Officer. We anticipate your start
date will be on or before February 14th, 2006. We believe you will be a
substantial contributor and look forward to growing the business with you.

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      As an acknowledgement of your acceptance, please sign one copy of this
letter and forward it to Carol Dane in Human Resources (fax: 781-890-5950). I
look forward to hearing from you.

Sincerely,

/s/ Yuchun Lee

Yuchun Lee
Chief Executive Officer

I ACCEPT THIS OFFER OF EMPLOYMENT AND THE TERMS OF NON-COMPETITION,
NON-DISCLOSURE AND DEVELOPMENTS AGREEMENT. THIS OFFER LETTER SETS FORTH THE
COMPLETE AND ENTIRE UNDERSTANDING REGARDING MY EMPLOYMENT AND SUPERCEDES ANY AND
ALL OTHER NEGOTIATIONS, PROPOSALS OR UNDERSTANDINGS, WHETHER WRITTEN OR ORAL.

/s/ Ralph Goldwasser                          February 2, 2006
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Ralph Goldwasser                              Date