Exhibit 32.1


                CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350

                             AS ADOPTED PURSUANT TO

                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the quarterly report on Form 10-Q of Franklin Street
Properties Corp. (the "Company") for the period ended June 30, 2006 as filed
with the Securities and Exchange Commission on the date hereof (the "Report"),
the undersigned, George J. Carter, President and Chief Executive Officer of the
Company, hereby certifies, pursuant to 18 U.S.C. Section 1350, that:

            (1)   the Report fully complies with the requirements of Section
                  13(a) or 15(d) of the Securities Exchange Act of 1934; and

            (2)   the information contained in the Report fairly presents, in
                  all material respects, the financial condition and results of
                  operations of the Company.

Date: August 2, 2006                    /s/ George J. Carter
                                        -------------------------------------
                                        George J. Carter
                                        President and Chief Executive Officer