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                                                                   Exhibit 10.31

                                     VIACELL

December 15, 2003
With clarifications, finalized March 11, 2004

Stephen P. Dance
1147D La Rochelle Terrace
Sunnyvale, CA 94089

Dear Steve,

On behalf of ViaCell, Inc. (the "Company"), I am pleased to extend an offer of
employment to you. You have made an outstanding impression throughout the
interview process, 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, Finance and 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 2004
                         fiscal year will be $235,000.00 per year payable in
                         bi-weekly installments of $9,038.46. For the 2004
                         fiscal year and thereafter, this base salary shall be
                         subject to adjustment. As agreed, your compensation
                         package will be reviewed when the company successfully
                         completes its initial public offering. Currently our
                         standard annual salary review process occurs each
                         January for senior management.

                         In addition, you will be eligible to participate in the
                         Management Bonus Plan at an annual target of $50,000 of
                         base salary, payable annually based on agreed to
                         company and individual performance objectives.
                         Eligibility will begin January 2004. Your bonus payout
                         is determined based on achievement of both corporate
                         and individual goals.
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S. Dance Revised Offer
December 15, 2003
Page 2


RELOCATION               You will receive a lump sum bonus towards your
                         relocation assistance in the amount of $30,000.

                         Additionally, the company understands that you may
                         incur some costs as a result of your family's
                         relocation that will not be covered by your spouse's
                         relocation package. ViaCell will cover reasonable
                         relocation costs that are not covered by other
                         assistance and which are made necessary by your
                         employment with us in Boston. Please work with Kathleen
                         Hayes to set up a budget for necessary relocation
                         expenses.

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 equals the fair
                         market value of our Common Stock as determined by the
                         Board of Directors on your date of hire; your fair
                         market value price is $5.00 per share. The Options will
                         vest quarterly over four years beginning on the last
                         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 additional
                         stock options ("Performance Based OPTIONS Options") to
                         purchase 100,000 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; your fair
                         market value price is $5.00 per share. The Performance
                         Based Options shall become exercisable as to 25% of the
                         shares on each of the fourth, fifth, sixth and seventh
                         anniversary of the date of grant; provided, however,
                         that 25,000 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", to be determined), 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", to be determined), then 50,000 such shares shall
                         become fully vested and exercisable until the
                         expiration
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S. Dance Revised Offer
December 15, 2003
Page 3

                         of such options or until they sooner terminate in
                         accordance with their terms. The milestones above are
                         determined relative to a goal of $1 billion market
                         valuation. The 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. 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 here
                         means (i) your continued failure to substantially
                         perform your duties provided you are reasonably
                         notified of such failure and 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.
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S. Dance Revised Offer
December 15, 2003
Page 4

CHANGE OF CONTROL        Upon a Change of Control with the Company, the 100,000
                         Performance Based Options granted on the date of hire
                         shall become fully vested and exercisable.

                         If in connection with a change in control described
                         above, 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. 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.

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, 401k, 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.

ELIGIBILITY FOR          The Immigration Reform and Control Act of 1986 requires
EMPLOYMENT               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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S. Dance Revised Offer
December 15, 2003
Page 5




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 Kathleen Hayes 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/ Stephen Dance
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Signature                                   Date

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Social Security Number                      Start Date