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                                                                  Exhibit 10.3.1

                                    VIACELL

October 26, 2002

Jeffrey Sacher
25 Lawrence Drive
Short Hills, NJ  07078

Dear Jeff,

On behalf of ViaCell, Inc. (the "Company"), I am pleased to extend an offer of
employment to you. You have made an outstanding impression, and we feel
confident that you will become a valuable asset to the company. Information
about ViaCell as well as the details of our offer of employment are summarized
below.

VIACELL MISSION            To provide the highest quality cellular medicines for
                           the treatment of human diseases.

VIACELL CULTURE            We are dedicated to delivering revolutionary
                           medicines through development of important new
                           therapeutic applications. Every day you will be
                           contributing to a technology that is enriching of the
                           lives of people in the future. We hire innovative
                           thinkers, with the skills and capabilities to thrive
                           on a high quality, success driven team.

POSITION                   Senior Vice President, Chief Financial Officer,
                           Reporting to Marc Beer, Chief Executive Officer
                           This position is a key factor in ViaCell's continued
                           success, and I am confident that it will be an
                           exciting opportunity for you as well.

COMPENSATION               The starting base salary for this position for the
                           2002 fiscal year will be $210,000.00 per year payable
                           in bi-weekly installments of $8,076.92. For the 2003
                           fiscal year and thereafter, this base salary shall be
                           subject to adjustment.

                           In addition, you will be eligible to participate in
                           the Executive Management Bonus Plan at an annual
                           target of 30% of base salary, payable annually based
                           on agreed to company and individual performance
                           objectives. Please note that you will not be eligible
                           for the Executive Management Bonus for calendar year
                           2002 and eligibility will begin January 2003. Please
                           see enclosed plan document for details.

TERM                       This letter indicates a 1-year contract,
                           automatically renewable for additional 1-year periods
                           unless either party to the contract gives notice of
                           termination at least 3 months prior to the end of
                           period.

STOCK OPTIONS              As an incentive for you to participate in the
                           Company's future growth, you will receive, subject to
                           approval by our Board of Directors, options to
                           purchase up to 125,000 shares of our Common Stock
                           (the "Options"). The Options will be incentive stock
                           options ("ISO's") to the extent allowable under the
                           Internal Revenue Code. The exercise price of the
                           Options will equal the fair market value of our
                           Common Stock as determined by the Board of Directors
                           on your date of hire. The Options will vest quarterly
                           over four years beginning on the last
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                           day of the first quarter after the date of
                           commencement of your employment. The Options will be
                           granted under the Company's 1998 Equity Incentive
                           Plan pursuant to an ISO certificate or nonstatutory
                           stock option ("NSO") certificate, as appropriate,
                           shall have a term of ten years and contain such
                           additional terms as shall be determined by the Board
                           of Directors of the Company or the Compensation
                           Committee thereof.

ADDITIONAL STOCK           In addition, the Company shall grant to you
OPTIONS                    additional stock options ("Performance Based
                           Options") to purchase 75,000 shares of Common Stock
                           as NSO's. The exercise price of the options will
                           equal the fair market value of our Common Stock as
                           determined by the Board of Directors on your date of
                           hire. The Performance Based Options shall become
                           exercisable as to 25% of the shares on each of the
                           fourth, fifth, sixth and seventh anniversaries of the
                           date of grant; provided, however, that 20,000 such
                           shares shall become fully vested and exercisable on
                           each of the first and second anniversaries of the
                           initial public offering; and if at any time within 24
                           months after the expiration of any lock up period
                           imposed by the underwriters in connection with the
                           Company's initial public offering of Common Stock,
                           the average closing prices of the Company's common
                           stock over a period of 30 consecutive trading days,
                           as reported by the Nasdaq National Market, or any
                           exchange on which the Company's Common Stock is then
                           traded, equals or exceeds $26.00 per share
                           ("Milestone A"), or if at any time within 36 months
                           after the expiration of any lock up period imposed by
                           the underwriters in connection with the Company's
                           initial public offering of Common Stock, the average
                           closing prices of the Company's common stock over a
                           period of 30 consecutive trading days, as reported by
                           the Nasdaq National Market, or any exchange on which
                           the Company's Common Stock is then traded, equals or
                           exceeds $34.00 per share ("Milestone B"), then 35,000
                           such shares shall become fully vested and exercisable
                           until the expiration of such options or until they
                           sooner terminate in accordance with their terms. The
                           $26.00 and $34.00 per share figures shall be adjusted
                           for stock splits, stock dividends and reverse stock
                           splits. The options shall have a term of ten years
                           from the date of grant, and contain such other terms
                           and conditions as are consistent with the form of NSO
                           certificate, most recently approved by the Board or
                           any authorized committee thereof for use under the
                           1998 Plan or as the Board or any such committee may
                           hereafter direct. Granting of these Performance Based
                           Options will not preclude you from participating in
                           other performance based option grant programs that
                           may be established within the Company.


ADDITIONAL EMPLOYMENT      ViaCell will provide for twelve months' severance pay
TERMS                      in the event of involuntary termination without cause
                           or voluntary termination for good reason. If the
                           Company shall terminate your employment without
                           "cause" or if you terminate your employment for "good
                           reason," then ViaCell will continue paying your base
                           salary and medical and dental benefit contributions
                           for a period of twelve months in accordance with its
                           regular payroll practices at such time, and you will
                           be entitled to receive, as of the date of
                           termination, an additional twelve months of vesting
                           of the two option awards granted at the time of hire
                           (i.e. as if Mr. Sacher had been employed by ViaCell
                           for an additional twelve months from the date of
                           termination). If the Company terminates your
                           employment with "cause," then ViaCell will continue
                           paying your base salary for a period of thirty days
                           and all options will cease to continue vesting as of
                           the date of termination. The term "cause" as used
                           herein means (i) your continued failure to
                           substantially perform your duties provided you are
                           reasonably notified of such failure and
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                           given reasonable time to correct such failure, (ii)
                           any misappropriation of funds, properties or assets
                           of the Company by you, (iii) any damage or
                           destruction of any property or assets of the Company
                           caused by you, whether resulting from your willful
                           actions or willful omissions or gross negligence;
                           (iv) your being convicted of a felony; or (v) any
                           material breach of your employment obligations or of
                           the Intellectual Property and Confidential
                           Information Agreement. The term "good reason" as used
                           here means any action by the Company without your
                           prior consent which results in (i) any material
                           diminution in your title, position, duties,
                           responsibilities or authority; or (ii) any breach by
                           the Company of any material provision contained
                           herein.

CHANGE OF CONTROL          Upon a Change in Control of the Company, as defined
                           below, in which the per share consideration to the
                           Company is at least $12.00 per share, within 24
                           months from the date you commence employment with the
                           company, the 75,000 Performance Based Options granted
                           on the date of hire shall become fully vested and
                           exercisable.

                           If in connection with a Change in Control, as defined
                           below, the company terminates your employment without
                           "cause" within twelve months of the change in control
                           or you voluntarily resign for "good reason", all
                           options granted as of that date shall become fully
                           vested and exercisable and ViaCell will continue
                           paying your base salary and benefits for a period of
                           twelve months following the date of termination,
                           without duplicating other amounts due under this
                           agreement. The options will continue to be subject to
                           the grant provisions under the 1998 Plan.

                           A "Change in Control" shall mean: (i) a merger,
                           consolidation or similar combination after which 50%
                           or more of the voting stock of the surviving
                           corporation is held by persons who were not
                           stockholders of the Company immediately prior to such
                           merger or combination; (ii) the sale, transfer or
                           other disposition of all or substantially all of the
                           Company's assets to one or more persons (other than
                           any wholly owned subsidiary of the Company) in a
                           single transaction or series of related transactions;
                           or (iii) any person or related group of persons
                           (other than the Company or a person that directly or
                           indirectly controls, is controlled by, or is under
                           common control with the Company) directly or
                           indirectly acquires beneficial ownership (determined
                           pursuant to Rule 13d-3 promulgated under the
                           Securities Exchange Act of 1934, as amended) of
                           securities possessing more than 50% of the total
                           combined voting power of the Company's outstanding
                           securities pursuant to a tender or exchange offer
                           made directly to the Company's stockholders.
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BENEFITS                   Because we care about the well being of our
                           employees, we are pleased to provide you with a
                           comprehensive offering of benefits. Our benefits
                           currently include medical, dental, life insurance,
                           three weeks vacation (accrued monthly and pro-rated
                           during your first calendar year of employment),
                           balance benefit, educational assistance and
                           flexible-spending accounts. Additional information
                           about these benefits is outlined in the enclosed
                           summary.

RELOCATION ASSISTANCE      In connection with your relocation to the
                           Massachusetts area, ViaCell agrees to provide the
                           following:

                           MOVING EXPENSES: ViaCell will pay for all actual
                           reasonable moving expenses for packing and shipping
                           household goods and two cars to the Massachusetts
                           area (arrangements to be made by ViaCell Human
                           Resources).

                           TEMPORARY HOUSING/TRAVEL/STORAGE: The company will
                           pay the actual costs of traveling for you and your
                           family to Massachusetts plus you will be entitled to
                           reimbursement for up to $20,000, or reasonable costs
                           related to temporary housing arrangements as agreed
                           to by you and ViaCell at the time of hire.

                           HOUSE HUNTING TRIPS: ViaCell will reimburse two
                           house-hunting trips for you and your spouse, for up
                           to three days with reasonable transportation, hotel
                           accommodations, and meal allowance of up to $25.00
                           per day per person.

                           REAL ESTATE FEE: ViaCell will reimburse all actual
                           reasonable real estate commissions (up to 6%) related
                           to the sale of your residence in New Jersey (all
                           monies will be grossed up to cover state and federal
                           tax liability).

                           CLOSING COSTS: ViaCell will reimburse for closing
                           costs on the purchase of a new home such as: title,
                           insurance property tax fees, transfer tax, tax
                           service/notary recording fees, appraisal and credit
                           report, and home inspection fees (all monies will be
                           grossed up to cover any applicable state and federal
                           tax liability).

                           Please be advised that relocation items will be
                           taxable income and only the Real Estate Fee and
                           Closing Costs will be grossed up to cover tax
                           liability. If you should for any reason voluntarily
                           terminate your employment with ViaCell within the
                           first 12 months of relocating to Massachusetts, you
                           will be obligated to reimburse ViaCell for any
                           relocation monies paid on your behalf.


ELIGIBILITY FOR            The Immigration Reform and Control Act of 1986
EMPLOYMENT                 requires ViaCell to review documentary evidence that
                           you are eligible for employment. This requirement
                           applies to US citizens, as well as foreign nationals.
                           A list of approved documents that are acceptable as
                           verification of employment eligibility are listed on
                           page two of the I-9 form which will be included with
                           your orientation packet. Please bring the appropriate
                           documents with you on your first day of employment.

EMPLOYMENT RELATIONSHIP    While we look forward to a long and mutually
                           beneficial relationship, you acknowledge that this
                           letter does not constitute a contract of employment
                           for any particular period of time and does not affect
                           the at-will nature of the employment relationship
                           with the company. Either you or ViaCell have the
                           right to terminate your employment at any time.
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We are very excited about the future of ViaCell and believe that the
opportunities presented will allow you significant personal and professional
growth. If you have any questions or concerns, please do not hesitate to contact
me anytime. We look forward to having you join our team!

Sincerely,

/s/ Marc Beer

Marc Beer
Chief Executive Officer

Please acknowledge your acceptance of this offer by signing a copy of this
document along with the Agreement Related to Intellectual Property and
Confidential Information and faxing it to Kristin Dickson at 617-247-6271. This
offer will remain in effect for a period of seven (7) calendar days from the
date of this letter.

/s/ Jeffrey Sacher
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Signature                                   Date

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Social Security Number                      Start Date