EX-32.1 4 ex321-hsiix20250930.htm EX-32.1
Exhibit 32.1
CERTIFICATION
Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
(Subsections (a) and (b) of Section 1350, Chapter 63 of Title 18, United States Code)
Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (subsections (a) and (b) of Section 1350, Chapter 63 of Title 18, United States Code), the undersigned officer of Heidrick & Struggles International, Inc., a Delaware corporation (the “Company”), does hereby certify that:
The Quarterly Report on Form 10-Q for the quarter ended September 30, 2025 (the “Form 10-Q”) of the Company fully complies with the requirements of section 13 (a) or 15 (d) of the Securities Exchange Act of 1934 and the information contained in the Form 10-Q fairly presents, in all material respects, the financial condition and results of operations of the Company.

Dated: | November 3, 2025 |  | /s/ Thomas L. Monahan III
|  |  | Thomas L. Monahan III
|  |  | Chief Executive Officer