UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-Q/A

Amendment No. 1

x      QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended June 30, 2013

OR

o  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from               to               

Commission File Number  001-33287

INFORMATION SERVICES GROUP, INC.

(Exact name of Registrant as specified in its charter)

Two Stamford Plaza

281 Tresser Boulevard

Stamford, CT 06901

(Address of principal executive offices and zip code)

Registrant’s telephone number, including area code: (203) 517-3100

Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes x  No o

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes x  No o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer or a non-accelerated filer. See definition of “accelerated filer and large accelerated filer” in Rule 12b-2 of the Exchange Act). (Check one):

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).    o  Yes  x  No

Indicate the number of shares outstanding of each of the issuer’s classes of common stock, as of the latest practicable date.

EXPLANATORY NOTE

This Form 10-Q/A, Amendment No. 1 is being filed solely for the purpose of correcting a scrivener’s error in Exhibits 32.1 and 32.2, Certification Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, of the Form 10-Q for the period ended June 30, 2013 that was filed on August 7, 2013.  In addition, as required by Rule 12b-15 under the Securities Exchange Act of 1934, as amended, new certifications by our principal executive officer and principal financial officer are filed as exhibits to this Amendment.

No other changes have been made to the Form 10-Q. This Amendment No. 1 to the Form 10-Q continues to speak as of the original filing date of the Form 10-Q, does not reflect events that may have occurred subsequent to the original filing date, and does not modify or update in any way the disclosures made in the original Form 10-Q.

Item 6. Exhibits.

* Previously filed as part of our Quarterly Report on Form 10-Q for the period ended June 30, 2013 with the Securities and Exchange Commission on August 7, 2013.

** Filed herewith.

2

SIGNATURES

In accordance with the requirements of the Exchange Act, the registrant caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

3