Bill Hellmuth, AIA, LEED AP, is an American architect who has designed several notable projects worldwide. Since 2005, he has been president of HOK, a global architecture, engineering and planning firm, while also heading its Washington, D.C., office.
In April 2016, Hellmuth succeeded Patrick MacLeamy as HOK’s CEO while continuing to serve as the firm’s president and design principal in Washington, D.C. 
Hellmuth received a Bachelor of Science (Architecture) degree from the University of Virginia, and, in 1977, a Master of Architecture from Princeton University, where he studied under Michael Graves. After leaving school, he joined Skidmore, Owings and Merrill. In 1991, he joined HOK (the "Hellmuth" in HOK was his uncle), and became president of the firm in 2005.
As a longtime champion of sustainable design, Hellmuth began integrating sustainability into projects long before LEED certification became commonplace.
Projects that Hellmuth has designed include:
- Greenland Dalian East Harbor Tower, Dalian, China (108 stories)
- Abu Dhabi National Oil Company Headquarters, Abu Dhabi, UAE (74 stories)
- King Abdullah Petroleum Studies and Research Center (KAPSARC) Residential Community, Riyadh, Saudi Arabia
- DC Consolidated Forensic Laboratory, Washington, D.C. (LEED Platinum)
- National Oceanic and Atmospheric Administration’s Center for Climate and Weather Prediction, Riverdale Park, Maryland
- Steven F. Udvar-Hazy Center, Chantilly, Virginia 
- The Collection at Chevy Chase, Chevy Chase, Maryland
Hellmuth is married and has two grown children.
- Dietsch, Deborah K. (November 17, 2008). "HOK's Bill Hellmuth: On top of the world".
- Forgey, Benjamin (January 9, 1999). "Two Modest, Modern Buildings; Pair Evidences Distinct Style ofWilliam Hellmuth".
- Arsenault, Haley (27 January 2016). "HOK Names Bill Hellmuth as Chief Executive Officer".
- Brennan, Vince (25 January 2016). "HOK names new CEO in succession plan". St. Louis Business Journal. Retrieved 18 March 2016.
- "Design Futures Council Announces 2014 Senior Fellows". DesignIntelligence. Retrieved 11 September 2014.
- "Grand Opening: The Collection at Chevy Chase". Retail Traffic Mag. May 1, 2006. Retrieved July 9, 2010.