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                                                                    Exhibit 10.8

July 12, 2006

BY EMAIL

Mr. Scott Krenz
826 W. Illinois Avenue
Palatine IL 60067

Dear Scott:

This letter will describe our mutual understanding regarding the termination of
your employment with Sapient Corporation ("Sapient" or the "Company").

Although the Company relieved you of your duties as Chief Financial Officer,
effective on May 11, 2006, you will remain a Sapient employee until August 10,
2006, or (if earlier) until you begin full-time employment with a third party
(the earlier of these dates being referred to as the "Exit Date"). You will
continue to receive your base salary and will remain eligible for Company
benefits until the Exit Date. In return, until the Exit Date you will make
yourself available to the Company for consultation and help in transitioning
your former job duties.

Additionally, you agree that, after the Exit Date and as may be reasonably
requested by the Company, you will assist the Company in consultations,
interviews, meetings, depositions, court appearances, administrative agency
proceedings and other matters that pertain to any actual or potential audit,
investigation, litigation or other dispute in which Sapient is (or may become) a
party and in which you are (or may become) an actual or potential deponent or
witness (collectively, referred to as "Dispute Proceedings").

Sapient will make reasonable efforts to accommodate your schedule and geographic
location in seeking your participation in Dispute Proceedings and will reimburse
you for any related reasonable expenses. In making these efforts, Sapient will
act in good faith and attempt to avoid major disruptions to your ability to
perform full-time employment duties that you may then have. Based on our mutual
understanding (as set forth in the paragraph above) that the Company can only
require your assistance in situations where you are (or may become) an actual or
potential deponent or witness in the Dispute Proceeding, you agree that the
Company will not be obligated to pay you further compensation in connection with
your participation. If the Company would like your assistance in any other
situation involving a Dispute Proceeding, you will have no obligation to agree.

RETURN OF SAPIENT PROPERTY

On or before the Exit Date, you will return all Sapient property (including
building and office access cards, credit and calling cards, laptop computers and
accessories and all other property belonging to the Company or its clients), as
well as all correspondence, files and confidential or proprietary information
(whether in hard or soft form) that pertain to the Company or its clients.

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FINAL PAY AND EXPENSE REIMBURSEMENT

Any outstanding balances you owe to the Company (for the Java Bean, commuter
passes, etc.) will be deducted from your last paycheck. Please note that your
last regular paycheck will be a "live" check, and will not be directly deposited
into your account, but will, instead, be given to you at the time of separation
or mailed to your home address.

On or before the Exit Date, you will submit any outstanding expense reports
(along with required receipts) to your manager. Approved expense reports will be
processed and reimbursement check(s) will be mailed to your home address in
accordance with Sapient's standard expense reimbursement policy.

COBRA BENEFITS CONTINUATION

After your employment terminates, you will have the right to continue your
medical and dental insurance pursuant to the provisions of the Consolidated
Omnibus Budget Reconciliation Act of 1985 ("COBRA"). The COBRA "qualifying
event" will be deemed to have occurred on the Exit Date. If you plan to continue
your COBRA option, Group Dynamic will send you a COBRA package that will explain
what the COBRA benefit is, how to elect this coverage and what it will cost you
to continue your benefits under COBRA. If you do not receive this package within
30 days from your termination of insurance coverage date, please call Group
Dynamic at 800-626-3539. If you do not elect COBRA, your coverage under
Sapient's medical and dental insurance for you (and, if applicable, your
dependent(s)) will end on the last day of the month in which the Exit Date
occurs.

STOCK OPTIONS AND RESTRICTED STOCK UNITS ("RSUS")

Your equity account with E*Trade will remain active following the end of your
employment in accordance with E*Trade's policies. (These policies currently
permit your account to remain active as long as you have Sapient shares in your
account.) You will receive a packet of information from E*Trade at your home
address within 30 days of the Exit Date. The packet will include a statement of
your exercisable options and vested RSUs, as well as relevant date and exercise
information. If you do not receive this packet within 30 days, please contact
E*Trade at 1-888-680-2132.

Pursuant to Sapient's equity incentive plans and your Sapient Stock Option
Agreement(s), you have three months from the Exit Date to exercise any options
that were exercisable as of your last day of employment. All such options that
you do not exercise within that three-month period automatically terminate. All
of your unvested RSUs will be cancelled upon the Exit Date.

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EMPLOYEE STOCK PURCHASE PLAN ("ESPP") AND 401(k) PLAN

If you participate in the Company's ESPP, the money held in your ESPP account
will be paid to you with your last paycheck. If you participate in the Sapient
401(k) Plan and you have a vested account balance of $1,000 or more, you may
either keep your vested balance in the Sapient Plan or request to have the
entire vested balance paid out to you or rolled over into another plan. [Note:
If your vested 401(k) account balance is under $1,000, you must request a
roll-over or distribution within 90 days of the Exit Date. Otherwise, the
balance will automatically be paid out to you and you will be subject to
penalties and tax withholdings for early distribution.] If you currently have a
401(k) loan outstanding, you will be able to continue paying off your 401(k)
loan directly to Fidelity. Fidelity will send you a loan coupon book within 30
days of the Exit Date that allows you to remit loan repayments. If you wish to
transfer your funds, please visit the Fidelity Web site at www.401k.com and
follow the instructions there to complete the transfer. If you have questions
related to your 401(k) Plan, please contact Fidelity at 1-800-890-4015.

ADDRESS CHANGES

If your address changes at any time between now and the end of the calendar
year, please notify Sapient's Payroll office at payroll@sapient.com. This
notification will help to ensure receipt of your W-2 in a timely manner at
year-end.

UNEMPLOYMENT COMPENSATION

Enclosed is a brochure explaining the process by which you may apply for
unemployment compensation benefits. Please note that receipt of this brochure
does not mean you will be eligible for such benefits.

CONTINUING NDA OBLIGATIONS

You are reminded of your continuing obligations to Sapient included in your
agreement regarding non-disclosure, non-solicitation, and non-competition (the
"NDA"). Sapient will provide you with an additional copy of your NDA, upon
request.

RELEASE OF CLAIMS

In consideration of the payments and other accommodations provided to you
hereunder, and by virtue of your signing this letter agreement, you hereby
knowingly and voluntarily release and forever discharge Sapient and its
officers, directors, stockholders, corporate affiliates, attorneys, agents and
employees (collectively, "Sapient Affiliates") of and from any and all claims,
known and unknown, you have or may have against Sapient or any Sapient Affiliate
as of the date of execution of this letter agreement (including, but not limited
to, any alleged violation of: Title VII of the Civil Rights Act of 1964, as
amended; the Civil Rights Act of 1991; Sections 1981 through 1988 of Title 42 of
the United States Code, as amended; the Employee Retirement

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Income Security Act of 1974, as amended; the Immigration Reform and Control Act,
as amended; the Americans with Disabilities Act of 1990, as amended; the Worker
Adjustment and Retraining Notification Act, as amended; the Occupational Safety
and Health Act, as amended; the Age Discrimination in Employment Act , as
amended; any federal, state or local civil or human rights law similar to those
included in the foregoing list; any other federal, state or local law,
regulation or ordinance; and any public policy, contract, tort or common law)
and any allegation for costs, fees or other expenses (including attorneys' fees)
incurred in these matters.

You affirm that you have not filed (or caused to be filed), nor are you a party
to, any claim, complaint or action, in any form, against Sapient or any Sapient
Affiliate. You further affirm that, through the period ending on the date of
this letter, you have received all leave (paid or unpaid), compensation, wages,
bonuses, commissions and benefits (collectively, "Compensation & Benefits") to
which you are entitled and that no other Compensation & Benefits are due to you,
except as provided in this letter agreement.

In addition, as a condition to receiving the benefits detailed in this letter
agreement, you agree to execute, as of the Exit Date, the Supplemental Release
of Claims attached hereto as Exhibit A (the "Supplemental Release").

AGE DISCRIMINATION IN EMPLOYMENT ACT: CONSIDERATION AND REVOCATION PERIODS

Please note that you have 21 days to consider the arrangements detailed in this
letter agreement and seven days to revoke your agreement to this letter
agreement after you have signed it. The terms described in this letter agreement
will not become effective until you sign and return it, and until the seven-day
revocation period expires. [Note: If the last day of the revocation period is a
Saturday, Sunday or legal holiday in the state in which you were employed on the
Exit Date, then such period will not expire until the next following day which
is not a Saturday, Sunday or legal holiday.]

If you do not sign and return a copy of this letter agreement within such 21-day
period (or if you revoke same within seven days after signing), then your
employment termination will be effective immediately upon the expiration of such
21-day period (or upon such revocation) and you will not have the right to
receive any of the benefits described in this letter agreement.

Any revocation must be submitted, in writing, to Seanna Balfe, Legal Counsel and
state substantially the following: "I hereby revoke my acceptance of our letter
agreement signed by me on [insert date] regarding the termination of my
employment." The revocation must be personally delivered to Ms. Balfe or sent to
her by other means for which you are able to produce written evidence of receipt
within such seven-day period by the Company (e.g., by means of certified or
registered mail, courier receipt, fax transmission cover sheet, e-mail "delivery
receipt," etc.). Ms. Balfe's address and notification information follow:
Sapient Corporation, 25 First Street, Cambridge, MA 02141 [fax: 617-621-1300;
e-mail: sbalfe@sapient.com].

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Please note that the release granted by you above in this letter agreement
applies, without limitation, to any rights or claims you may have under the Age
Discrimination in Employment Act , as amended (the "ADEA"), as well as any other
claims. You acknowledge that you have been given 21 days to consider this letter
agreement and such release. Sapient urges you to use as much of the time
afforded as you deem necessary, not only to consider this letter agreement and
the release contained herein, but also to consult with an attorney prior to
signing.

Consistent with the provisions of the ADEA and other federal discrimination
laws, nothing in this release will be deemed to prohibit you from challenging
the validity of this release under the federal age or other discrimination laws
(collectively with the ADEA, the "Federal Discrimination Laws") or from filing a
charge or complaint of age or other employment-related discrimination with the
Equal Employment Opportunity Commission (the "EEOC"), or from participating in
any investigation or proceeding conducted by the EEOC.

Further, nothing in this letter agreement or the release contained herein shall
be deemed to limit the Company's right to seek immediate dismissal of such
charge or complaint, on the basis that your signing of this letter agreement
constitutes a full release of any individual rights under the Federal
Discrimination Laws, nor the Company's right, to the extent permitted by law, to
seek restitution of the economic benefits provided to you under this letter
agreement, in the event that you successfully challenge the validity of this
release and prevail in any claim under the Federal Discrimination Laws.

You represent that you have carefully read this letter agreement, understand its
contents, are signing it freely and voluntarily and assent to all of the terms
and conditions hereof.

OTHER TERMS

You agree to keep the facts and terms described in this letter agreement
confidential and not to disclose any information concerning your termination,
except to the extent required by law. Additionally, you agree that you will not
disparage Sapient or any Sapient Affiliates to any third party.

The Company will cooperate in providing any of your prospective employers with
an appropriate reference regarding your employment at Sapient.

This letter agreement is governed by the laws of the Commonwealth of
Massachusetts, without regard to its conflict of law provisions. Should any
provision of this letter agreement (excluding the release language) be declared
illegal or unenforceable by any court of competent jurisdiction and cannot be
modified so as to be legal and enforceable, such provision shall immediately
become null and void, leaving the remainder or this letter agreement in full
force and effect.

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The parties agree that neither this letter agreement nor the furnishing of the
consideration for this release shall be deemed or construed at any time for any
purpose as an admission by either party of any liability or unlawful conduct of
any kind.

This letter agreement may not be modified, altered or changed except upon both
parties' express written consent, in which specific reference is made to this
letter agreement.

This letter agreement sets forth the entire agreement between the parties and
supersedes any prior agreements or understandings between the parties (except
your NDA, as referenced above).

We wish you the best in your future endeavors.

Sincerely,

/s/ Jerry A. Greenberg
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Jerry A. Greenberg, Co-Chairman & Chief Executive Officer

ACCEPTED AND AGREED TO:

/s/ Scott Krenz
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Scott Krenz

Date: August 10, 2006

Enclosures

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                                                                       EXHIBIT A

                         SUPPLEMENTAL RELEASE OF CLAIMS

In consideration of the covenants set forth in my agreement with Sapient
Corporation ("Sapient" or the "Company") dated July 12, 2006, regarding the
termination of my Sapient employment (the "Letter Agreement") and, more
particularly, the payments and other benefits provided to me thereunder, and for
other good and valuable consideration, I, Scott Krenz, hereby knowingly and
voluntarily affirm, on and as of the final day of my employment with the Company
(my "Exit Date") and to the fullest extent set forth in the Letter Agreement:

      1.    My release and discharge of any and all claims, known and unknown,
            that I have or may have against Sapient and any and all of its
            officers, directors, stockholders, corporate affiliates, attorneys,
            agents and employees (collectively, "Sapient Affiliates"); and

      2.    All of the representations, warranties and covenants made by me
            under the Letter Agreement in relation to such release and
            discharge.

/s/ Scott Krenz
---------------
Scott Krenz

Date:         August 10           , 2006
      ---------------------------
       [Insert Exit Date above]

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