Duff & Phelps (DUF) 10-K 2011 FY Annual report

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 annual report of Duff & Phelps Corporation (the “Company”) on Form 10-K for the period ended December 31, 2011 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Noah Gottdiener, Chairman of the Board & Chief Executive Officer of the Company, certify, to the best of my knowledge, pursuant to Rule 13a-14(b) under the Securities Exchange Act of 1934 and 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, 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 for the periods presented therein.

Date:	February 17, 2012	/s/ Noah Gottdiener
		NOAH GOTTDIENER
		Chairman of the Board & Chief Executive Officer