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                                                                   Exhibit 10.37


REVISED
July 23, 2001

Scott Semel
54 Knobhill Street
Sharon, MA 02067

Dear Scott:

We are very pleased that you are considering joining us at Ascential Software.
The purpose of this letter is to set forth our offer of employment. We propose
that you begin employment with Ascential Software in the capacity of Vice
President & General Counsel in our Westboro office, reporting to Peter Fiore,
President of Ascential Software and Peter Gyenes, CEO of Ascential Software
Corporation, with a starting date no later than August 20, 2001. You will also
serve as our Company's Corporate Secretary. Three months from your start date of
August 20, 2001 you will be eligible for salary and compensation review. This
position will also include four weeks of vacation.

Your salary, computed on an annual basis beginning on the date you become an
employee of the Company is $200,000, which will be paid, in equal semi-monthly
installments of $8333.00. You will be covered under our company health, dental,
life and long-term disability insurance benefit plans, effective on the first
day of your employment. Insurance programs are subject to change by the Company
without notice. Ascential Software also offers a 401(k) retirement savings
program with immediate enrollment eligibility. You will also participate in the
Executive Incentive Compensation Plan (EICP) at a rate of 35%. Should a Change
In Control (CIC) occur that also results in your termination or constructive
discharge, the vesting and exercise period for these 125,000 stock options will
be continued for one year beyond your termination date. Severance pay in the
amount of one years' base and on target earnings (EICP @ 35%) shall be paid
should a CIC, with resulting termination or constructive discharge, occur.

In addition to your base salary above, you will be recommended for a
nonqualified stock option under the Ascential Software Corporation Employee
Stock Option Plan to acquire 125,000 shares of the common stock of Ascential
Software Corporation. Options are granted to Ascential employees on the 15th
Ascential U.S. business day of each month ("the Grant Date"). If this option is
granted to you, it will be granted on the Grant Date occurring in the month
following the month in which your employment commences. You, of course, will be
under no obligation to exercise any stock options, which may be granted to you.

This offer of employment is contingent upon the following:

         -        Your signing of the Company's Employee
                  Confidential/Ownership/Nonsolicitation Agreement, in the form
                  attached.

         -        Your acceptance of this offer by signing this letter below.

         -        Your signing of the enclosed W-4 form.

         -        Within your first day of employment, you must provide for
                  examination proof of your legal right to work in the United
                  States and complete the Immigration Form I-9 as required by
                  the U.S. Immigration and Naturalization Service. These include
                  either 1) a U.S. passport, a U.S. certificate of citizenship,
                  a U.S. certificate of naturalization, an unexpired foreign
                  passport with attached employment authorization or an alien
                  registration card with photograph; OR 2) a state driver's
                  license, a state I.D. card, a U.S. military card AND a Social
                  Security card or a U.S. birth
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July 20, 2001
Page 2
Scott Semel

                  certificate. If you do not have proof of identification on the
                  first day of employment, you will be sent home to obtain the
                  documents. You will not be placed on the payroll until this
                  form is completed by a Company representative. If for any
                  reason you are unable to provide proof of your identity as
                  well as your legal right to work in the United States within
                  the first three days, the Company may terminate your
                  employment. From time to time after your first day of
                  employment, you may be asked to provide proof of your identity
                  as well as your legal right to work in the United States.
                  Employment may be contingent upon approval of an Export
                  License granted by the U.S. Department of Commerce, if
                  required.


This offer of employment is for employment "at will", which means that it is not
for any specific period of time and your employment may be terminated with or
without cause by yourself or the Company at any time and for any reason.

As an employee of Ascential Software, you also agree to comply with company
policies, procedures and standards of conduct that may be established by the
Company.

This offer of employment contains all of the terms and conditions of your
employment with the Company and supersedes any and all prior, oral or written
representations or agreements made by anyone employed by, or associated with,
the Company.

The terms of this offer, if accepted, will become your terms of employment and
can only be added to or modified by a written document signed by the Vice
President of Human Resources, Human Resources Director or the President of the
Company.

Please be advised that this offer of employment is valid only to 7 business
days. Please acknowledge your acceptance by signing and dating this letter and
returning it to before 7 business days. In addition, please complete and return
all of the enclosed new hire forms to the Human Resources Staffing Department
prior to beginning your employment or no later than 3 days after your date of
hire. Enclosed for your convenience in returning the offer letter and related
material is a self-addressed envelope. Please bring all of your new hire
paperwork, required identification, Non-Disclosure Agreement with you on your
first day of employment for verification and witnessing by your manager.

Scott, we are very excited at the prospect of you joining our executive team.
Your industry expertise and leadership competencies will be a wonderful
attribute to Ascential. Should you have any questions regarding this offer,
please call Eileen Bergquist at (508) 366-3888 X3215.

Sincerely,

/s/ Eileen Bergquist

Eileen Bergquist - VP Human Resources

Enclosures
AGREED ON THE  25th DAY OF July, 2001

ANTICIPATED START DATE: August 20, 2001

SIGNED: /s/ Scott Semel