Steve:

Senior Vice President, WorldwideSales.  You will report directly to me and subject to fulfillment ofany condition imposed by this letter agreement, you will begin this new positionon April 30, 2007 (the “Start Date”).  It is the Company’s intentionthat you will work out of the Company’s office in Sunnyvale, California,although you may be transferred to Seattle at the Company’sdiscretion.

| 3101      Western Ave, Seattle, WA 98121 TEL (206) 315-7500   FAX (206)      315-7501     www.isilon.com |
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| (i)   | In      respect to any material misrepresentation by you concerning the subject      matter of this letter; |
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| (ii)   | In      respect to your material breach or material non-fulfillment of any      agreement or covenant contained in this letter and/or any other agreement      entered into between the Company andyou; |
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| (iii)   | In      respect to any breach or non-fulfillment of any agreement or covenant by      you to ***; or |
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| (iv)   | On      account of an action or omission by you which constitutes willful      misconduct or is knowingly fraudulent or deliberately      dishonest. |
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| ●   | This      offer is contingent upon successful references and      background check. |
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| ●   | Base      Salary:  You will be paid $225,000 on an annual      basis.  Your salary will be payable every two weeks pursuant to      the Company’s regular payroll policy and will be subject to applicable      withholding taxes.  Your base salary may be increased in the      future, but will not be decreased, by the  Company. |
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| ●   | Bonus:  You      are eligible for a quarterly bonus of $31,250 ($125,000 total annual bonus      potential or higher with Company performance above plan) upon successful      achievement of MBOs and Company goals.  The bonus is split      equally between achievement of MBOs and certain revenue/EBIT goals, as      determined by the Compensation Committee of the Board of Directors (the      “Compensation Committee”). |
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| ●   | Commission      Plan:  You will be eligible for commissions based on      Isilon’s global sales revenue.  The 2007 plan calls for $*** of      total revenue, with $*** of revenue contribution in Q2, $*** in Q3, and      $*** of revenue in Q4.  Target annual commission is $125,000 at      plan, plus upside above target as notedbelow: |
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| Annual      Revenue | %      of Target | Commission      % | Commission      $ | %      Increase over Target | Total      Compensation* |
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| ***                 | 100%             | ***               | $125,000          |                        | $475,000                 |
| ***                 | 110%             | ***               | $300,000          | ***                         | $650,000                 |
| ***                 | 125%             | ***               | $450,000          | ***                         | $800,000                 |
| ***                 | 150%             | ***               | $650,000          | ***                         | $1,000,000               |

| ●   | Initial Option      Grant.  Following the commencement of your employment,      the Company will recommend that the Compensation Committee grant you a      nonstatutory stock option to purchase 360,000 shares of the Company’s      Common Stock.  The exercise price will be the market closing      price (or the closing bid, if no sales are reported) of the Company’s      Common Stock on The NASDAQ Global Market on the date of the grant, which      will be on the first new hire stock option approval date following your      Start Date, unless such date falls within a quarterly trading blackout      period, in which case the date of grant will be the first day the      Company’s trading window opens following that quarterly blackout      period.  The option may be exercised in accordance with the      following vesting schedule:  25% of the shares will vest on the      twelve (12) month anniversary of your Start Date and 1/12th      of the remaining shares will vest quarterly thereafter, such that the      option will be fully vested and exercisable on the four-year anniversary      of your Start Date.  Vesting will, of course, depend on your      continued employment with the Company.  The option will be a      nonstatutory stock option and will be subject to the terms of the      Company’s 2006 Equity Incentive Plan (the “2006 Plan”) and Notice of Grant      of Stock Option, each of which is attached  hereto. |
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| ●   | Subsequent Option      Grants. At the discretion of the Company’s Board of Directors (or      its designated committee), you may be eligible to receive additional      grants of stock options or purchase rights from time to time in the      future, on such terms and subject to such conditions as the Compensation      Committee shall determine as of the date of such  grant. |
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| ●   | Insurance Benefits. The      Company will provide you with standard medical and dental insurance      benefits according to Company policy.  Benefits will commence      the first of the month following your first day of full-time employment      with the company. |
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| ●   | Vacation. You will be      entitled to vacation according to Company  policy. |
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| ●   | Indemnification.  The      Company currently indemnifies all officers and directors to the maximum      extent permitted by law, and you will enter into the Company’s standard      form of Indemnification Agreement giving you such      protection.  Pursuant to the Indemnification Agreement, the      Company will agree to advance any expenses for which indemnification is      available to the extent allowed by applicable law.  You shall be      covered by all directors and officers insurance policies in place during      your employment, providing protection at least comparable to present      coverage. |
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| ●   | House      hunting trip for up to 4 days for you and your family (includes airfare,      hotel, rental car, meals in accordance with Isilon’s travel      policy); |
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| ●   | Household      move to include goods/cars and storage for up to 60  days; |
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| ●   | Temporary      housing for up to 60 days.  Temporary housing beyond 60 days      will be by mutual agreement; and |
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| ●   | Closing      costs in connection with the sale of your current residence in California      and the purchase of a primary residence in the Seattle area will be      reimbursed up to $200,000. |
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| ●   | Upon      the date of the relocation (the “Relocation Date”) with your family to      Seattle, if requested by the Company, the Company will recommend that the      Compensation Committee grant you a nonstatutory stock option to purchase      40,000 shares of the Company’s Common Stock (the “Relocation      Grant”).  The exercise price for this Relocation Grant will be      the market closing price (or the closing bid, if no sales are reported) of      the Company’s Common Stock on The NASDAQ Global Market on the date of the      grant, which will be on the first new hire stock option approval date      following the Relocation Date, unless such date falls within a quarterly      trading blackout period, in which case the date of grant will be the first      day the Company’s trading window opens following that quarterly blackout      period.  The Relocation Grant (if provided) will vest in      accordance with the following schedule:  25% of the shares will      vest on the twelve (12) month anniversary of the Relocation Date and      1/12th      of the remaining shares will vest quarterly thereafter, such that the      Relocation Grant will be fully vested and exercisable on the four-year      anniversary of the Relocation Date.  For purposes of this      clause, the Relocation Date shall be understood to mean the later of the      dates on which (a) you have closed on the purchase of a primary residence      in the Seattle area; and (b) your immediate family members are all      permanently living in the Seattle area.50% of your quarterly MBO payout      will accrue but not be paid unless and until you have relocated to      Seattle, to occur no later than July 1, 2008, provided that the Company      has requested such relocation.  If the Company does not request      such relocation prior to April 15, 2008, any accrued MBO payments will be      made to you on or before May 15,2008. |
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| ●   | General.  In      the event of termination of your employment under any circumstances you      will not be entitled to any benefits (other than those you are due under      applicable law) except as set forth in this  Section. |
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| ●   | Termination.  If      the Company terminates your employment for any reason other than for Cause      (as defined below), or you resign your position with the Company for Good      Reason (as defined below), subject to your signing and not revoking a      release of claims substantially similar to a form attached hereto as      Exhibit A, you will be entitled to receive an immediate lump-sum payment      in an amount equal to your then current base salary or $225,000 on an      annualized basis, whichever is higher.  Furthemore, you shall be      entitled to receive reimbursement of COBRA premiums for a period of six      (6) months (the “Severance Period”). To the extent that you obtain health      benefits from another employer or pursuant to a consulting relationship      during the Severance Period, if applicable, reimbursement of COBRA      premiums will cease to the extent that you ceased to make COBRA payments      because of such health benefits.  You agree that you will notify      the Company of your obtaining employment or a consulting agreement, and      the relevant terms thereof, during the Severance Period.  You      will not be entitled to any additional payments, salary, bonus or benefits      in the event of termination forCause. |
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| ●   | Section      409A.  Notwithstanding anything to the contrary in this      letter agreement, any cash severance payments otherwise due to you      pursuant to the foregoing paragraph or otherwise on or within the      six-month period following your termination will accrue during such      six-month period and will become payable in a lump sum payment on the date      six (6) months and one (1) day following the date of your termination,      provided, that such cash severance payments will be paid earlier, at the      times and on the terms set forth in the applicable provisions of the      foregoing paragraph, if the Company reasonably determines that the      imposition of additional tax under Section 409A of the Internal Revenue      Code of 1986, as amended, will not apply to an earlier payment of such      cash severance payments.  In addition, this letter agreement      will be deemed amended to the extent necessary to avoid imposition of any      additional tax or income recognition prior to actual payment to you under      Code Section 409A and any temporary or final Treasury Regulations and      guidance promulgated thereunder and the parties agree to cooperate with      each other and to take reasonably necessary steps in this      regard. |
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| ●   | “Cause” for termination      will exist if you are terminated for any of the following conduct that has      caused or is reasonably expected to result in material injury to the      Company:  (i) your willful failure substantially to perform your      duties or responsibilities to the Company or deliberate violation of a      Company policy; (ii) your commission of any act of fraud, embezzlement,      dishonesty or any other willful misconduct; (iii) unauthorized use or      disclosure by you of any proprietary information or trade secrets of the      Company or any other party to whom you owe an obligation of nondisclosure      as a result of your relationship with the Company; or (iv) your willful      breach of any of your obligations under any written agreement or covenant      with the Company. |
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| ●   | “Good Reason” is defined      as (1) any action by the Company or any successor that results in a      diminution of your position, authority, duties, responsibilities,      compensation or benefits without your written consent, (2) any failure by      the Company or any successor to comply with any provision of this letter      agreement, (3) the Company’s or any successor’s requiring you to be based      at any office or location more than 30 miles from your office location;      provided however, that a future relocation to Seattle shall not constitute      Good Reason, or (4) any failure by a successor to the Company to assume      the Company’s material obligations under this letter      agreement. |
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| ●   | Conditions.  Any      payments made will be subject to applicable tax withholding, and your      receipt of such payments shall be subject to your executing the Company’s      (or it’s successors) standard form release of claims releasing the Company      and it’s successor(s) from claims relating to your employment relationship      and termination of thatrelationship. |
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