UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 8-K

                                 CURRENT REPORT
                       Pursuant to Section 13 or 15(d) of
                       The Securities Exchange Act of 1934

          Date of Report (Date of earliest event reported): May 3, 2007


                             NetScout Systems, Inc.
             ------------------------------------------------------
             (Exact Name of Registrant as Specified in its Charter)

                                    Delaware
             ------------------------------------------------------
                 (State or Other Jurisdiction of Incorporation)

       0000-26251                                         04-2837575
------------------------                       ---------------------------------
(Commission File Number)                       (IRS Employer Identification No.)


310 Littleton Road, Westford, Massachusetts                  01886
-------------------------------------------    ---------------------------------
 (Address of Principal Executive Offices)                  (Zip Code)

                                 (978) 614-4000
          -------------------------------------------------------------
              (Registrant's Telephone Number, Including Area Code)

                                 Not Applicable
          -------------------------------------------------------------
          (Former Name or Former Address, If Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to
simultaneously satisfy the filing obligation of the registrant under any of the
following provisions:

[ ] Written communications pursuant to Rule 425 under the Securities Act (17
    CFR 230.425)

[ ] Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17
    CFR 240.14a-12)

[ ] Pre-commencement communications pursuant to Rule 14d-2(b) under the
    Exchange Act (17 CFR 240.14d-2(b))

[ ] Pre-commencement communications pursuant to Rule 13e-4(c) under the
    Exchange Act (17 CFR 240.13e-4(c))




ITEM 2.02. RESULTS OF OPERATIONS AND FINANCIAL CONDITION.

     The following information and the Exhibit attached hereto shall not be
deemed "filed" for purposes of Section 18 of the Securities Exchange Act of
1934, as amended (the "Exchange Act") or otherwise subject to the liabilities of
that section, nor shall it be deemed incorporated by reference in any filing
under the Securities Act of 1933, as amended, or the Exchange Act, except as
expressly set forth by specific reference in such filing.

     On May 3, 2007, NetScout Systems, Inc. (the "Company") issued a press
release regarding its financial results for the quarter and fiscal year ended
March 31, 2007, its expectations of future performance and its intention to hold
a conference call regarding these topics. The Company's press release is
furnished as Exhibit 99.1 to this report and is incorporated herein by
reference.

Use of Non-GAAP Financial Information

Non-GAAP Financial Information

     To supplement the financial measures presented in the Company's press
release in accordance with generally accepted accounting principles in the
United States ("GAAP"), the Company also presented non-GAAP measures relating to
operating margin and earnings per share, which figures were adjusted from
amounts determined based on GAAP to exclude a charge related to certain payments
to be made to Narendra Popat, a co-founder and former Chairman of the Company in
connection with his retirement and advisory agreement with the Company. The
non-GAAP financial measures appeared in the statements in the press release that
the charge of $1.4 million or $0.03 per share related to Mr. Popat's agreement
accounted for a five percentage point reduction in operating margin, and,
excluding such charge, non-GAAP operating margin would have been 12% for the
fourth quarter and non-GAAP earnings per diluted share would have been $0.26 per
share for the full fiscal year 2007, representing growth of 43% year-over-year
and exceeding full year guidance of 40% growth. The Company believes these
non-GAAP financial measures will enhance the reader's overall understanding of
the Company's current financial performance and the Company's prospects for the
future. Presenting the GAAP measures on their own would not be indicative of the
Company's core operating results and would not provide a meaningful comparison
to prior periods. The Company gave significant weight to the fact that the
charges related to Mr. Popat's retirement and advisory agreement were
non-recurring in deciding to present such information. The Company relies on
these non-GAAP financial measures generally in connection with evaluating and
running its business operations, including managing sales efforts, measuring the
attainment of the Company's internal financial goals, making compensation
decisions and managing headcount requirements. The Company gave greater
prominence in the release to the amounts determined based on GAAP. The
presentation of this non-GAAP information is not meant to be considered superior
to, in isolation from or as a substitute for results prepared in accordance with
GAAP.


ITEM 9.01. FINANCIAL STATEMENTS AND EXHIBITS.

(d)  Exhibits.

     The Company hereby furnishes the following exhibit:

     99.1 Press release dated May 3, 2007.




                                   SIGNATURES

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                   NETSCOUT SYSTEMS, INC.

                                   By: /s/ David P. Sommers
                                       --------------------
                                       David P. Sommers
                                       Chief Financial Officer and
                                       Senior Vice President, General Operations


     Date: May 3, 2007




                                  EXHIBIT INDEX

Exhibit Number        Description
--------------        ----------------------------------------------------------
99.1                  Press release dated May 3, 2007.