Exhibit 10.11

Performance Share Award Agreement

Granted Under NxStage Medical, Inc. 2014 Omnibus Incentive Plan

1. Grant of Performance Shares.

This agreement evidences the grant by NxStage Medical, Inc., a Delaware corporation (the “Company”), to the Participant listed below of performance shares representing the conditional right to receive restricted stock units (“RSUs”), as outlined below:

Except as otherwise indicated by the context, “Participant” shall be deemed to include any person who acquires these performance shares validly under their terms.

These performance shares are granted in consideration of employment services rendered and to be rendered by the Participant to the Company. These performance shares are subject to the terms of this agreement and the Company’s 2014 Omnibus Incentive Plan (the “Plan”), a copy of which is furnished to the Participant with this agreement. Any capitalized term that is not defined in this agreement shall have the meaning ascribed to it in the Plan.

2. Vesting.

*Targets are in millions. Performance goals exclude non-operating activities such as divestitures, and other non-operating items that may arise that were not included in the plan. Performance goals should be measured by applying the same accounting principles, tax laws or other laws or provisions in effect at the time of preparing the performance goals set forth above, without regard to whether there was a change in application of accounting principles, tax laws or other laws or provisions at a later date.

Performance in-between specific goals will result in the number of RSUs earned to be interpolated between the corresponding amounts in the table above.

“Eligible Participant” means a Participant that is, and at all times since the Grant Date has been, an employee, officer or director of, or consultant or advisor to, the Company or an Affiliate of the Company.

Any earned RSUs will be granted pursuant to, and be subject to the terms and conditions set forth in, a separate restricted stock unit agreement to be entered into between the Company and the Participant.

3. Withholding Taxes.

This Section 3 only applies to Participants who are Employees. The Company may deduct from payments of any kind otherwise due to the Participant all applicable federal, state or local withholding taxes required by law to be withheld in respect of these performance shares or the RSUs.

4. Termination.

If the Participant ceases to be an Eligible Participant for any reason, all of the then unvested performance shares, unearned RSUs and unvested Shares will be forfeited immediately and automatically, without the payment of any consideration to the Participant, effective as of the time that the Participant ceases to be an Eligible Participant.

5. Transfer Restrictions.

These performance shares may not be sold, assigned, transferred, pledged or otherwise encumbered by the Participant, either voluntarily or by operation of law, except by will or the laws of descent and distribution or pursuant to a domestic relations order in settlement of marital property rights.

*  *  *

IN WITNESS WHEREOF, the Company has caused this agreement to be executed by its duly authorized officer under its corporate seal.

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PARTICIPANT’S ACCEPTANCE

The undersigned hereby accepts the terms and conditions of this agreement and acknowledges receipt of a copy of the Company’s 2014 Omnibus Incentive Plan and related prospectus.

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