(b) On January 22, 2013, Michael Miller, Jr. resigned as President, International of NxStage Medical, Inc. The Company and Mr. Miller have agreed that his resignation will constitute a termination of employment as of February 1, 2013.

(d) On January 22, 2013, the Board of Directors of NxStage Medical, Inc. appointed Robert G. Funari to serve as a director. The appointment of Mr. Funari fills the vacancy following David S. Utterberg's resignation from the Board earlier this month. Mr. Funari was not appointed to any committees of NxStage's Board of Directors.

Mr. Funari will be entitled to receive compensation for his service on the Board of Directors consistent with NxStage's director compensation program for non-employee directors, as described under the heading Director Compensation in NxStage's proxy statement for its 2012 Annual Meeting of Stockholders as filed with the Securities and Exchange Commission on April 24, 2012, which description is incorporated in this Form 8-K by reference.

In connection with Mr. Funari's appointment to the Board of Directors, he and NxStage will enter into NxStage's standard form of indemnification agreement for directors, the form of which was previously filed as Exhibit 10.21 to NxStage's registration statement on Form S-1 (File No. 333-126711).

A copy of NxStage's January 24, 2013 press release announcing Mr. Funari's appointment is attached hereto as Exhibit 99.1 and is incorporated in this report by reference.

(d) Exhibits

                  Exhibit
                  Number    Description

                  99.1      Press Release dated January 24, 2013