February 25, 2010

Date of Report (Date of earliest event reported)

SONUS NETWORKS, INC.

(Exact Name of Registrant as Specified in its Charter)

DELAWARE	001-34115	04-3387074
(State or Other Jurisdiction	(Commission File Number)	(IRS Employer
of Incorporation)		Identification No.)

7 TECHNOLOGY PARK DRIVE, WESTFORD, MASSACHUSETTS 01886

(Address of Principal Executive Offices) (Zip Code)

(978) 614-8100

(Registrant’s telephone number, including area code)

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 (see General Instruction A.2. below):

¨ 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))

The information in this Current Report on Form 8-K 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”), otherwise subject to the liabilities of that Section or incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.

Item 2.02. Results of Operations and Financial Condition.

On February 25, 2010, Sonus Networks, Inc. issued a press release reporting financial results for the quarter and year ended December 31, 2009. A copy of the press release is furnished as Exhibit 99.1 hereto.

Item 9.01. Financial Statements and Exhibits.

(d)	Exhibits

	The following exhibit relating to Item 2.02 shall be deemed to be furnished, and not filed:

	99.1	Press release of Sonus Networks, Inc. dated February 25, 2010 reporting its financial results for the quarter and year ended December 31, 2009.

SIGNATURE

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 hereunto duly authorized.

Date: February 25, 2010	SONUS NETWORKS, INC.

	By:
		/s/ Jeffrey M. Snider
		Jeffrey M. Snider
		Senior Vice President and General Counsel

Exhibit Index

99.1

Press release of Sonus Networks, Inc. dated February 25, 2010 reporting its financial results for the quarter and year ended December 31, 2009.