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, 2006


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

                                    Delaware
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                 (State or Other Jurisdiction of Incorporation)

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


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


                                 (978) 614-4000
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              (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 7.01. REGULATION FD DISCLOSURE.

     The following information 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, 2006, NetScout Systems, Inc. (the "Company") participated in the
conference call in connection with the announcement of their earnings with
respect to the fiscal quarter and fiscal year ended March 31, 2006. During such
call, the Company disclosed that it believed that it would be able to deliver
annual earnings per share growth of 40% to 60% in each of fiscal years 2007 and
2008.

     The Company also disclosed that, with respect to its long-term business
model, on a GAAP basis it expects to be able to maintain gross profit margins in
the range of 73 to 76%. The company expects to attain total operating expenses
to range from 53% to 58%, comprised of 14% to 16% in research and development
expenses, 32% to 35% in sales and marketing expenses and 7% to 9% in general and
administrative expenses. The Company also disclosed that it expected operating
margins to reach at least 15% and is targeting 20% on the high end of the range.
Finally, the Company disclosed that it expected to continue operating margin
expansion through fiscal year 2007 and beyond.

Safe Harbor:
------------

Forward-looking statements in this report are made pursuant to the safe harbor
provisions of Section 21E of the Securities Exchange Act of 1934 and other
federal securities laws. Investors are cautioned that statements in this report,
which are not strictly historical statements, including the plans, objectives
and future financial performance of NetScout, constitute forward-looking
statements which involve risks and uncertainties. Actual results could differ
materially from the forward-looking statements. Risks and uncertainties which
could cause actual results to differ include, without limitation, risks and
uncertainties associated with the Company's relationships with strategic
partners, dependence upon broad-based acceptance of the Company's network
performance management solutions, the Company's ability to achieve and maintain
a high rate of growth, introduction and market acceptance of new products and
product enhancements such as the delivery of nGenius product platform probes and
software solutions, High Definition Performance Management functionality, the
analytic solutions acquired from Quantiva and the implementation of the
Company's CDM Technology strategy, the ability of the Company to take advantage
of service provider opportunities, competitive pricing pressures, reliance on
sole source suppliers, successful expansion and management of direct and
indirect distribution channels and dependence on proprietary technology, and
risks of further slowdowns or downturns in economic conditions generally and in
the market for network performance management solutions specifically. For a more
detailed description of the risk factors associated with the Company, please
refer to the Company's Annual Report on Form 10-K for the fiscal year ended
March 31, 2005 and its quarterly report on Form 10-Q for the quarter ended
December 31, 2005 on file with the Securities and Exchange Commission. NetScout
assumes no obligation to update any forward-looking information contained in
this report or with respect to the announcements described herein.






                                   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, 2006