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                                                                   EXHIBIT 10.31

October 9, 2002

Robert A. Shipp
c/o Critical Path
350 The Embarcadero
San Francisco, CA 94105

Dear Al,

On behalf of Critical Path, Inc. (the "Company"), I am pleased to offer you the
position of President. Speaking for myself, as well as other members of the
Company's management team, we are all very impressed with your credentials and
we look forward to your future success in this position.

The terms of your employment with the Company are set forth below:

POSITION          You will be the President of the Company with worldwide
                  responsibility for Sales, Field Marketing, the Professional
                  Services Organization, and Sales Engineering. You will work
                  out of the Company's offices in San Francisco and report to
                  William E. McGlashan, Jr., Chief Executive Officer and
                  Chairman of the Board of Directors. This is an exempt
                  position.

                  You agree to the best of your ability and experience that you
                  will at all times loyally and conscientiously perform all of
                  the duties and obligations required of and from you pursuant
                  to the express and implicit terms hereof, and to the
                  reasonable satisfaction of the Company. During the term of
                  your employment, you further agree that you will devote all of
                  your business time and attention to the business of the
                  Company.

START DATE        Subject to fulfillment of any conditions imposed by this
                  letter agreement, you will commence this new position with the
                  Company on Thursday, October 10, 2002. Your new hire
                  orientation will take place at 9:15am on your Start Date at
                  our Headquarters office in San Francisco.

COMPENSATION      Your base salary will be $350,000 on an annualized basis. Your
                  salary will be payable in two equal payments per month
                  pursuant to the Company's regular payroll practices.

BONUS             You will be eligible to participate in the 2002 and 2003
                  Critical Path Sales Incentive Bonus Plan. Your on-target bonus
                  earnings at 100% attainment is $350,000 annually. Fifty
                  percent of your bonus is based on achievement of the Company's
                  revenue goals, and 50% is based on achievement of the
                  Company's expense goals. The Company's revenue goals must be
                  achieved before there is any bonus payment, as discussed in
                  the Plan. In addition you will be eligible for an additional
                  $350,000 bonus for performance beyond 100% attainment and
                  based on mutually agreed goals.

REVIEW            Your base salary will be reviewed annually as part of the
                  Company's salary review process. However, nothing in this
                  provision changes the at-will nature of the employment
                  relationship.

                                                             Critical Path, Inc.
                                                                    Confidential
                                                                          Page 1

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BENEFITS          The Company will provide you and your eligible dependents with
                  generous Medical, Dental, and Vision benefits. You will also
                  receive Short-term Disability, Long-term Disability, and Life
                  Insurance. In addition, the Company offers employees the
                  opportunity to participate in its Flexible Spending Account,
                  Employee Assistance Program, 401(k) Plan, and Employee Stock
                  Purchase Plan. A complete overview of benefits will be
                  presented to you on October 10, 2002.

PAID TIME OFF     You will receive 18 paid days off per year for the first four
                  complete years of service. This Paid Time Off will accrue at
                  the rate of 6 hours per pay period, or 12 hours per month.

STOCK OPTIONS     In connection with the commencement of your employment, the
                  Company will recommend that the Board Compensation Committee
                  grant you an option to purchase 2,000,000 shares of the
                  Company's Common Stock ("Shares") with an exercise price equal
                  to the closing price of Critical Path's stock on the last
                  trading day prior to the date of Grant. These Shares will vest
                  over four years, with 12.5% vesting on your six-month
                  anniversary with the Company, and 1/48th of the original grant
                  amount vesting monthly thereafter. Vesting will, of course,
                  depend on your continued employment with the Company. These
                  Shares will be subject to the terms of the applicable Company
                  Stock Option Plan and the Stock Option Agreement between you
                  and the Company.

                  In the event of a Change of Control of the Company, any
                  unvested Shares originally granted will vest immediately
                  should your employment be terminated without Cause, or if you
                  terminate your employment for Good Reason, each such event
                  occurring within twelve (12) months of such Change of Control,
                  all as such terms are defined in Appendix A.

SEVERANCE         To the extent you are terminated for any reason without cause,
                  you will receive, upon termination, a severance payment equal
                  to nine (9) months' base salary. Such severance benefit,
                  however, is not applicable until after your six-month
                  anniversary with the Company.

PROOF OF RIGHT TO WORK

                  For purposes of federal immigration law, you will be required
                  to provide to the Company documentary evidence of your
                  identity and eligibility for employment in the United States.
                  A list of acceptable documents is available for your
                  reference. Please have your identity and employment
                  eligibility document(s) with you for your new hire
                  orientation.

PROPRIETARY INFORMATION AND INVENTIONS AGREEMENT

                  Your acceptance of this offer and commencement of employment
                  with the Company is contingent upon the execution and
                  submission of the Company's Proprietary Information and
                  Inventions Agreement ("Proprietary Agreement"), a copy of
                  which has been provided to you with this offer letter.

AT-WILL EMPLOYMENT

                  Notwithstanding the Company's obligation described herein,
                  your employment with the Company will be on an "at-will"
                  basis, meaning that either you or the Company may terminate
                  your employment at any time for any reason or no reason,
                  without further obligation or liability.

DISPUTE RESOLUTION PROCEDURE

                  You and the Company ("the parties") agree that any dispute
                  arising out of or related to the employment relationship
                  between them, including the termination of that relationship
                  and any allegations of unfair or discriminatory treatment
                  arising under state or federal law or otherwise, that cannot
                  be resolved through the Company's informal grievance
                  procedure, shall be resolved by final and binding arbitration
                  in San Francisco, California,

                                                             Critical Path, Inc.
                                                                    Confidential
                                                                          Page 2

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                  except where the law specifically forbids the use of
                  arbitration as a final and binding remedy. The following
                  dispute resolution shall apply:

                  (a)   The complainant shall provide the other party with a
                        written statement of the claim identifying any
                        supporting witnesses or documents and the requested
                        relief.

                  (b)   The respondent shall furnish a statement of the relief,
                        if any, that it is willing to provide, and identify
                        supporting witnesses or documents. If the matter is not
                        resolved, the parties shall submit the dispute to
                        nonbinding mediation, paid for by the Company, before a
                        mediator to be selected by the parties.

                  (c)   If the matter is not resolved through mediation, the
                        parties agree that the dispute shall be resolved by
                        binding arbitration. If the parties are unable to
                        jointly select an arbitrator, they will obtain a list of
                        arbitrators in San Francisco County, California, from
                        the Federal Mediation and Conciliation Service and
                        select an arbitrator by striking names from that list.

                  (d)   The arbitrator shall have the authority to determine
                        whether the conduct complained of in section (a) of this
                        section violates the complainant's rights and, if so, to
                        grant any relief authorized by law; subject to the
                        exclusions of section (g) below. The arbitrator shall
                        not have the authority to modify, change, or refuse to
                        enforce the terms of any employment agreement between
                        the parties, or change any lawful policy or benefit
                        plan.

                  (e)   The Company shall bear the costs of the arbitration if
                        you prevail. If the Company prevails, you will pay half
                        the cost of the arbitration or $500, whichever is less.
                        Each party shall pay its own attorney's fees, unless the
                        arbitrator orders otherwise pursuant to applicable law.

                  (f)   ARBITRATION SHALL BE THE EXCLUSIVE FINAL REMEDY FOR ANY
                        DISPUTE BETWEEN THE PARTIES, SUCH AS DISPUTES INVOLVING
                        CLAIMS FOR DISCRIMINATION OR HARASSMENT (SUCH AS CLAIMS
                        UNDER THE FAIR EMPLOYMENT AND HOUSING ACT, TITLE VII OF
                        THE CIVIL RIGHTS ACT OF 1964, THE AMERICANS WITH
                        DISABILITIES ACT, OR THE AGE DISCRIMINATION IN
                        EMPLOYMENT ACT), WRONGFUL TERMINATION, BREACH OF
                        CONTRACT, BREACH OF PUBLIC POLICY, PHYSICAL OR MENTAL
                        HARM OR DISTRESS, OR ANY OTHER DISPUTES, AND THE PARTIES
                        AGREE THAT NO DISPUTE SHALL BE SUBMITTED TO ARBITRATION
                        WHERE THE COMPLAINANT HAS NOT COMPLIED WITH THE
                        PRELIMINARY STEPS PROVIDED FOR IN SECTIONS (a) AND (b)
                        ABOVE.

                  (g)   The parties agree that the arbitration award shall be
                        enforceable in any court having jurisdiction to enforce
                        this agreement, so long as the arbitrator's findings of
                        fact are supported by substantial evidence on the whole
                        and the arbitrator has not made errors of law; however,
                        either party may bring an action in a court of competent
                        jurisdiction regarding or related to inventions that you
                        may claim to have developed prior to joining the
                        Company, pursuant to California Labor Code Section 2870
                        ("Disputes Related to Inventions"). The parties further
                        agree that for Disputes Related to Inventions which the
                        parties have elected to submit to arbitration, each
                        party retains the right to seek preliminary injunctive
                        relief in court in order to preserve the status quo or
                        prevent irreparable injury before the matter can be
                        heard in arbitration.

OFFER CONDITIONS

                  This offer is null and void if not accepted or declined by
                  close of business on Thursday, October 10, 2002. This offer is
                  also contingent upon receiving your completed employment
                  application and the successful results of our independent
                  verification of your application.

                                                             Critical Path, Inc.
                                                                    Confidential
                                                                          Page 3

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We are delighted to be able to extend you this offer and look forward to working
with you. To indicate your acceptance of the Company's offer, please sign and
date this letter in the space provided below and return it to the Human
Resources department (if by fax, then to 415.541.2301), along with a signed and
dated copy of the Proprietary Agreement. This letter, together with the
Proprietary Agreement, constitute the full, complete, and exclusive agreement
between you and the Company regarding the matters herein and supersedes any
prior representations or agreements, whether written or oral. This letter may
not be modified or amended except by a written agreement, signed by the Company
and by you.

ACCEPTED AND AGREED:                        CRITICAL PATH, INC.

Name:_______________________________        By: /s/ William E. McGlashan, Jr.
                                                --------------------------------
                                                    William E. McGlashan, Jr.
                                                    Chief Executive Officer and
Signed: /s/ Robert Allen Shipp                      Chairman of the Board of
        ----------------------------                Directors

Date:_______________________________

                                                             Critical Path, Inc.
                                                                    Confidential
                                                                          Page 4

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Date: October 10, 2002

                                   APPENDIX A

"Change of Control" shall mean the consummation of one of the following: (i) the
acquisition of 50% or more of the outstanding stock of the Company pursuant to a
tender offer validly made under any federal or state law (other than a tender
offer by the Company); (ii) a merger, consolidation or other reorganization of
the Company (other than a reincorporation of the Company), if after giving
effect to such merger, consolidation or other reorganization of the Company, the
shareholders of the Company immediately prior to such merger, consolidation or
other reorganization do not represent a majority in interest of the holders of
voting securities (on a fully diluted basis) with the ordinary voting power to
elect directors of the surviving entity after such merger, consolidation or
other reorganization; (iii) the sale of all or substantially all of the assets
of the Company to a third party who is not an affiliate of the Company.

"Cause" shall mean (i) failure or refusal to perform a directive of the Chief
Executive Officer or of the Board of Directors of the Company that is consistent
with your duties and responsibilities as set forth in paragraph 1 hereof
(provided, that the Company provides to you written notice specifying the nature
of such failure or refusal and the actions needed to be taken by you to cure the
same and such failure or refusal is not cured by you within thirty (30) days of
receipt of such notice), (ii) you shall have been determined to be guilty of
willful misconduct or be in material violation of your fiduciary obligations to
the Company (provided, that the Company provides to you written notice
specifying the nature of such breach and actions needed to be taken by you to
cure same and such breach is not cured by you within ten (10) days of receipt of
such notice), (iii) you perform your duties in a grossly negligent manner, or
(iv) are convicted of any crime that has a material adverse impact on (A) your
ability to perform your duties hereunder, (B) the Company or (C) the Company's
business.

"Good Reason" shall be deemed to occur if (a)(1) there is a material adverse
change in employee's position causing such position to be of significantly less
stature or of significantly less responsibility, (2) there is a change in title,
(3) employee no longer reports to the Chief Executive Officer, (4) a material
reduction of employee's base salary compensation, (5) employee's refusal to
relocate to a facility or location more than fifty (50) miles from the Company's
current location; and (b) within the sixty (60) day period immediately following
such material change or reduction employee elects to terminate his employment
voluntarily.

                                                             Critical Path, Inc.
                                                                    Confidential
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