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                                                                    EXHIBIT 99.1



                                                  April 2, 2001


Mr. Earl Galleher
47 Norwich Road
Wellesley, Massachusetts  02481

Dear Earl:

     The purpose of this letter agreement (the "Agreement") is to confirm the
terms regarding your separation of employment with Akamai Technologies, Inc.1/
("Akamai" or the "Company"). As more fully set forth below, Akamai desires to
provide you with a severance package in exchange for certain agreements by you.

     1.  SEPARATION OF EMPLOYMENT. You acknowledge that your employment with
Akamai will terminate effective April 6, 2001 (the "Separation Date"), and
further that from and after the Separation Date, you shall have no authority and
shall not represent yourself as an employee or agent of Akamai.

     2.  SEVERANCE PACKAGE. In exchange for the mutual covenants set forth in
this letter, on the eighth day after your execution of this Agreement, provided
that you have not exercised your right of rescission under the Older Worker
Benefits Protection Act ("OWBPA"), as set forth in Section 6 below, Akamai
agrees to accelerate the vesting of 393,750 shares of restricted stock that was
issued to you under the Company's Second Amended and Restated 1998 Stock
Incentive Plan (the "Plan") and the Restricted Stock Agreement ("RSA") between
you and the Company. The Company will exercise its Purchase Option (as defined
in the RSA) with respect to all shares of restricted stock that are not vested
as of the Separation Date and are not accelerated pursuant to this Agreement,
i.e., 236,250 shares. This Section 2 shall constitute written notice of the
Company's exercise of its Purchase Option. You agree that within ten days of
your execution of this Agreement, you will tender to the Company the certificate
or certificates representing the shares as to which the Company is exercising
its Purchase Option. As soon as practicable after receipt and cancellation of
the repurchased shares, the Company will pay you the original purchase price for
those shares, or $9,581.62.

     Except as set forth in this Section 2, all of the terms, rights,
obligations and conditions of the Plan that you were eligible for or
participated in during your employment with Akamai, and any documents executed
by you pursuant to the Plan are hereby incorporated by reference and shall
survive the signing of this Agreement. You acknowledge and agree that from and
after the Separation Date, you shall not have any rights to vest in any stock
options or restricted stock under any Akamai stock or stock option plan (of
whatever name or kind) that you participated in or were eligible to participate
in during your employment.

     You acknowledge and agree that the Severance Package provided in this
Agreement is not otherwise due or owing to you under any Akamai policy or
practice, and that the Severance Package to be provided to you is not intended
to, and shall not constitute, a severance plan, and shall confer no benefit

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1/ For the purposes of this Agreement, the parties agree that the term "Akamai"
is intended to include Akamai Technologies, Inc. and any other divisions,
affiliates and subsidiaries, and its and their respective officers, directors,
agents and assigns.


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Letter Agreement for Earl Galleher
April 2, 2001
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on anyone other than the parties hereto. You further acknowledge that except for
(i) the specific consideration set forth in this Agreement, (ii) wages owed for
work performed up to the Separation Date, and (iii) accrued vacation pay in
accordance with Akamai's vacation policy, you are not and shall not in the
future be entitled to any other compensation including, without limitation,
other wages, commissions, bonuses, vacation pay, holiday pay, or any other form
of compensation or benefit.

     Notwithstanding anything to the contrary in this Agreement, upon timely
completion of the forms required by COBRA, you may continue, at your sole
expense, your medical and dental insurance coverage after the Separation Date to
the extent permitted by COBRA. The COBRA "qualifying event" shall be deemed to
be the Separation Date.

     3.  CONFIDENTIALITY/NON-SOLICITATION/OTHER OBLIGATIONS BY YOU.

          (i) You expressly acknowledge and agree that you have returned to
Akamai all Akamai documents (and any copies thereof) and property; you shall
abide by the provisions of the Non-Competition and Non-Solicitation Agreement
and the Invention and Non-Disclosure Agreement that you signed when you began
your employment at Akamai Technologies, Inc. (the terms of which are hereby
incorporated by reference and shall survive the signing of this Agreement and
copies of which are attached hereto as EXHIBIT A);

          (ii) You expressly acknowledge and agree that you will not, without
Akamai's express authorization, access, attempt to access or otherwise interfere
with Akamai's electronic information systems, including but not limited to
Akamai's computer, voice mail, or e-mail systems;

          (iii) You and Akamai acknowledge and agree that all information
relating in any way to the negotiation of this Agreement, including the terms
and amount of consideration provided for in this Agreement, shall be held
confidential by the parties and, except as mandated by state or federal law or
court order, shall not be publicized or disclosed to any person (other than an
immediate family member, legal counsel or financial advisor, provided that any
such individual to whom disclosure is made agrees to be bound by these
confidentiality obligations), business entity or government agency (other than a
business entity or government agency which employs you, provided that the only
terms that you are permitted to reveal to such employers are those contained in
your Non-Competition and Non-Solicitation Agreement and the Invention and
Non-Disclosure Agreement).

          (iv) You expressly acknowledge and agree that you will not make any
statements that are professionally or personally disparaging about, or adverse
to, the interests of Akamai (including its officers and directors) including,
but not limited to, any statements that disparage any person, product, service,
finances, financial condition, capability or any other aspect of the business of
Akamai, and that you will not engage in any conduct which is intended to harm
professionally or personally the reputation of Akamai (including its officers
and directors). Akamai's officers and directors will be informed that they may
not make any statements that are professionally or personally disparaging about
you.

     5.  FUTURE COOPERATION. You agree that until December 31, 2001 you shall
cooperate fully with Akamai in connection with any matter or event relating to
your employment or events that occurred during your employment, including,
without limitation, in the defense or prosecution of any claims or actions not
in existence or which may be brought or threatened in the future against or on
behalf of Akamai, including any claims or actions against its officers,
directors and employees. Your cooperation in connection with such matters,
actions and claims shall include, without limitation, being available, upon
reasonable notice, to meet with Akamai regarding matters in which you have been
involved, and any contract matters or audits; to prepare for any proceeding
(including, without limitation, depositions,


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Letter Agreement for Earl Galleher
April 2, 2001
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consultation, discovery or trial); to provide affidavits; to assist with any
audit, inspection, proceeding or other inquiry; and to act as a witness in
connection with any litigation or other legal proceeding affecting Akamai. You
shall be reimbursed for any reasonable out-of-pocket expenses incurred in
connection with providing such cooperation under this Section. You further agree
that should you be contacted (directly or indirectly) by any person or entity
(for example, by any party representing an individual or entity) adverse to
Akamai, you shall promptly notify Steve Heinrich at Akamai.

     6.  RELEASE OF CLAIMS/GALLEHER. You hereby agree and acknowledge that by
signing this letter and accepting the Severance Pay to be provided to you, and
other good and valuable consideration provided for in this Agreement, you are
waiving your right to assert any form of legal claim against Akamai (as defined
in the first paragraph of this Agreement) whatsoever for any alleged action,
inaction or circumstance existing or arising from the beginning of time through
the Separation Date related to your employment and/or termination of employment
with Akamai. Your waiver and release herein is intended to bar any form of legal
claim, charge, complaint or any other form of action (jointly referred to as
"Claims") against Akamai seeking any form of relief including, without
limitation, equitable relief (whether declaratory, injunctive or otherwise), the
recovery of any damages or any other form of monetary recovery whatsoever
(including, without limitation, back pay, front pay, compensatory damages,
emotional distress damages, punitive damages, attorneys fees and any other
costs) against Akamai, for any alleged action, inaction or circumstance existing
or arising through the Separation Date related to your employment and/or
termination of employment with Akamai.

     Without limiting the foregoing, you specifically waive and release Akamai
from:

     **   Claims under any state or federal discrimination, fair employment
          practices or other employment related statute, regulation or executive
          order (as they may have been amended through the Separation Date)
          prohibiting discrimination or harassment based upon any protected
          status including, without limitation, race, national origin, age,
          gender, marital status, disability, veteran status or sexual
          orientation. Without limitation, specifically included in this
          paragraph are any Claims arising under the federal Age Discrimination
          in Employment Act, the Older Workers Benefit Protection Act, the Civil
          Rights Acts of 1866 and 1871, Title VII of the Civil Rights Act of
          1964, the Civil Rights Act of 1991, the Equal Pay Act, the Americans
          With Disabilities Act and any similar Massachusetts or other state
          statute.

     **   Claims under any other state or federal employment related statute,
          regulation or executive order (as they may have been amended through
          the Separation Date) relating to wages, hours or any other terms and
          conditions of employment. Without limitation, specifically included in
          this paragraph are any Claims arising under the Fair Labor Standards
          Act, the Family and Medical Leave Act of 1993, the National Labor
          Relations Act, the Employee Retirement Income Security Act of 1974,
          the Consolidated Omnibus Budget Reconciliation Act of 1985 (COBRA) and
          any similar Massachusetts or other state statute, including any
          applicable payment of wages statutes.

     **   Claims under any state or federal common law theory including, without
          limitation, wrongful discharge, breach of express or implied contract,
          promissory estoppel, unjust enrichment, breach of a covenant of good
          faith and fair dealing, violation of public policy, defamation,
          interference with contractual relations, intentional or negligent
          infliction of emotional distress, invasion of privacy,
          misrepresentation, deceit, fraud or negligence.

     **   Any other Claim arising under state or federal law.

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Letter Agreement for Earl Galleher
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     Notwithstanding the foregoing, this section does not release Akamai from
any obligation expressly set forth in this Agreement. You acknowledge and agree
that, but for providing this waiver and release, you would not be receiving the
Severance Package being provided to you under the terms of this Agreement.

     Notwithstanding anything to the contrary in this Agreement, you expressly
reserve and do not release or waive any rights that you might otherwise have (i)
under any insurance policy, including without limitation Akamai's Directors and
Officers Liability Insurance Policy, and/or (ii) under any indemnification
provisions in Akamai's articles of incorporation or by-laws or board
resolutions, including the indemnification provisions of Akamai's Amended and
Restated Certificate of Incorporation, and/or (iii) to any benefits under the
Employee Retirement Income Security Act of 1974 (ERISA) or any ERISA benefit
plan.

     Notwithstanding anything to the contrary in this Agreement, in the event
that any officer or director of Akamai makes any statements that are
professionally or personally disparaging about you or adverse to your interests,
including, but not limited to, any statements that disparage you, your finances,
financial condition, capability or any other aspect of your employment with
Akamai, or engages in any conduct which is intended to harm your reputation
professionally or personally, the promise given in Section 3(iv) by you shall be
null and void as to that to that officer or director.

     Notwithstanding anything to the contrary in this Agreement, in the event
that any officer or director of Akamai asserts or pursues against you any claim
or cause of action referred to in Section 6, the release given to that officer
or director in this Section 7 by you shall be null and void, and you may assert
any and all defenses and claims of any kind whatsoever against that officer or
director that would have been available if you had not executed this Agreement.

     BECAUSE YOU ARE OVER FORTY (40) YEARS OF AGE, YOU HAVE SPECIFIC RIGHTS
UNDER THE OLDER WORKERS BENEFITS PROTECTION ACT ("OWBPA"), WHICH PROHIBITS
DISCRIMINATION ON THE BASIS OF AGE, AND THAT THE RELEASES SET FORTH IN THIS
SECTION ARE INTENDED TO RELEASE ANY RIGHT THAT YOU MAY HAVE TO FILE A CLAIM
AGAINST AKAMAI ALLEGING DISCRIMINATION ON THE BASIS OF AGE.

     IT IS AKAMAI'S DESIRE AND INTENT TO MAKE CERTAIN THAT YOU FULLY UNDERSTAND
THE PROVISIONS AND EFFECTS OF THIS LETTER. TO THAT END, YOU HAVE BEEN ENCOURAGED
AND GIVEN THE OPPORTUNITY TO CONSULT WITH LEGAL COUNSEL FOR THE PURPOSE OF
REVIEWING THE TERMS OF THIS LETTER. CONSISTENT WITH THE PROVISIONS OF OWBPA,
AKAMAI IS PROVIDING YOU WITH TWENTY-ONE DAYS (UNTIL APRIL 23, 2001) IN WHICH TO
CONSIDER AND ACCEPT THE TERMS OF THIS AGREEMENT BY SIGNING BELOW AND RETURNING
IT TO STEVE HEINRICH, AKAMAI TECHNOLOGIES, INC., 500 TECHNOLOGY SQUARE, 5TH
FLOOR, CAMBRIDGE, MA 02139. IN ADDITION, YOU MAY RESCIND YOUR ASSENT TO THIS
AGREEMENT IF, WITHIN SEVEN (7) DAYS AFTER YOU SIGN THIS AGREEMENT, YOU DELIVER A
NOTICE OF RESCISSION TO STEVE HEINRICH AT AKAMAI. TO BE EFFECTIVE, SUCH
RESCISSION MUST BE HAND DELIVERED OR POSTMARKED WITHIN THE SEVEN (7) DAY PERIOD
AND SENT BY CERTIFIED MAIL, RETURN RECEIPT REQUESTED, TO STEVE HEINRICH, AKAMAI
TECHNOLOGIES, INC., 500 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139.

     7.  LIMITED RELEASE OF CLAIMS/AKAMAI. In consideration of the promises
contained herein, and other good and valuable consideration, Akamai (as defined
in Section 1 of this Agreement) hereby releases and forever discharges you from
and any all Claims (as defined in the prior paragraph), which Akamai had, now
has, or may have in the future, relating in any manner to the performance by you
of your duties as an employee of Akamai so long as acts were within the scope of
your authority and you in fact were acting within the scope of your authority in
the performance of such duties.


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Letter Agreement for Earl Galleher
April 2, 2001
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     Notwithstanding the foregoing, this paragraph shall not release you from
any obligation set forth in this Agreement or other documents incorporated
herein.

     8.  ENTIRE AGREEMENT/CHOICE OF LAW/ENFORCEABILITY. You acknowledge and
agree that, with the exception of the Non-Competition and Non-Solicitation
Agreement and the Invention and Non-Disclosure Agreement, this Agreement
supersedes any and all prior or contemporaneous oral and/or written agreements
between you and Akamai, and sets forth the entire agreement between you and
Akamai. No variations or modifications hereof shall be deemed valid unless
reduced to writing and signed by the parties hereto. If there is any
inconsistency between the provisions of this Agreement and any prior or
contemporaneous oral and/or written agreements between you and Akamai, the
provisions of this Agreement shall govern. This Agreement shall be deemed to
have been made in the Commonwealth of Massachusetts, shall take effect as an
instrument under seal within Massachusetts, and shall be governed by and
construed in accordance with the laws of the Commonwealth of Massachusetts,
without giving effect to conflict of law principles. You agree that any action,
demand, claim or counterclaim relating to the terms and provisions of this
Agreement, or to its breach, shall be commenced in Massachusetts in a court of
competent jurisdiction, and you further acknowledge that venue for such actions
shall lie exclusively in Massachusetts and that material witnesses and documents
would be located in Massachusetts. The provisions of this letter are severable,
and if for any reason any part hereof shall be found to be unenforceable, the
remaining provisions shall be enforced in full. Both parties further agree that
any action, demand, claim or counterclaim shall be resolved by a judge alone,
and both parties hereby waive and forever renounce the right to a trial before a
civil jury.

     By executing this Agreement, you are acknowledging that you have been
afforded sufficient time to understand the terms and effects of this letter,
that your agreements and obligations hereunder are made voluntarily, knowingly
and without duress, and that neither Akamai nor its agents or representatives
have made any representations inconsistent with the provisions of this letter.

     If the foregoing correctly sets forth our understanding, please sign, date
and return both signed copies of this letter to me at Akamai by April 23, 2001.
One signed copy will be returned to you.

                                     Very truly yours,

                                     AKAMAI TECHNOLOGIES, INC.

                                     By: /s/ Steven P. Heinrich
                                        ------------------------------
                                        Steven P. Heinrich,
                                        Vice President, Human Resources

                                        Dated: April 2, 2001

Confirmed, Agreed and Acknowledged:


 /s/ Earl Galleher
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Earl Galleher


Dated:  April 2, 2001