Exhibit 10.2

December 23, 2009

Michael Piraino

VIA ELECTRONIC MAIL

Dear Michael:

We are pleased to offer you the following position with Accelrys, Inc. (the “Company”). It is our hope that you will become a part of our exciting and innovative organization. The following will confirm the terms of our offer of employment to you:

Position/Location: You will assume the position of Accelrys’ Senior Vice President and Chief Financial Officer reporting to the Company’s Chief Executive Officer. This position is based in our San Diego headquarters and will require your relocation to the San Diego area. Prior to your relocation to San Diego you will commute to our headquarters with regularity. Reasonable lodging expenses in connection with such commute will be reimbursed by the Company.

Compensation: Your compensation in the above position will include an annual base salary of $300,000.00, less applicable withholdings, paid during the Company’s regular payroll periods. In addition, you will be eligible to participate in our Management Incentive Plan (the “Plan”) designed to allow you to earn initially up to an additional 50% at plan of your annual base salary in incentive compensation upon achievement of corporate performance objectives as determined by the Board. For fiscal year 2010, your bonus will be pro-rated for the number of months during the fiscal year during which you were employed by the Company.

Employment: As the Chief Financial Officer of the Company, you will be eligible to participate in our comprehensive employee benefits package, including health, disability and life insurance; participation in our 401(k) retirement savings plan; and vacation benefits. You will also be eligible for any other benefits provided to our senior executives including long term care and enhanced life and long term disability insurance benefits.

Equity Award: We are recommending to the Human Resources Committee of the Board of Directors (“Committee”) that you receive a non-qualified option to purchase 125,000 shares of common stock. The stock option will be priced as of the date of your commencement of employment (the “Vesting Commencement Date”) and shall vest as follows: 1/4 of the stock underlying the option shall vest on the one year anniversary of the Vesting Commencement Date and 1/48^th of the stock underlying the option shall vest monthly thereafter so that the option shall be fully vested four years from the Vesting Commencement Date. We are also recommending to the Committee that you be awarded 60,000 restricted stock units. 1/3 of the stock underlying the units will vest upon the first anniversary of your Vesting Commencement Date; another 1/3 will vest on the second anniversary of your Vesting Commencement Date and the final 1/3 will vest on the third anniversary of your Vesting Commencement Date. All equity awards contemplated by this paragraph will be issued pursuant to the Company’s 2004 Stock Incentive Plan.

Accelrys reviews all executives after the close of each fiscal year. Among other matters, it considers the award of additional equity, based on performance and other factors as determined by the Committee. You will be eligible for review under this program, with any recommendation subject to the approval of the Committee at its discretion.

Employment Agreement: Concurrently herewith the Company is providing you with an employment agreement setting forth the terms of your employment.

Relocation Terms/Legal Review Fees: Accelrys Inc. will agree to pay for reasonable and customary expenses associated with your relocation to the San Diego area, up to a maximum of $125,000, upon your acceptance of this offer and commencement of your employment with us. Relocation expenses must be approved in advance and can include but not be limited to the following items:

To the extent that any reimbursable relocation expenses would constitute taxable income to you, such amounts will paid within thirty days of the receipt of a written reimbursement request and all supporting invoices and documentation, but in no event later than March 15, 2011

Please note that should you voluntarily terminate your employment with the company (without “Good Reason” as defined in your employment agreement) prior to 2 years from the date of your relocation to San Diego, as defined by final payment of relocation related expenses, you must repay to the company all monies paid to you or on your behalf in conjunction with your relocation.

The Company will also reimburse up to $2,500 in customary and reasonable legal expenses incurred in review of this offer letter and your employment agreement.

Confidentiality: As with all our employees, you will be required to execute and be bound by the Company’s Invention and Non-Disclosure Agreement which you will find enclosed for your review and execution prior to your commencement of employment with the Company.

Proposed Start Date: We would appreciate your acceptance of our offer by execution of the accompanying employment and confidentiality/invention assignment agreements, with an agreed upon start date of January 5, 2010.

I look forward to your joining the Accelrys Inc. team and your involvement in what we are confident represents an exciting and professionally rewarding venture.