Heisler is perhaps best known for his more than 70 cover portraits for Time magazine. His iconic portraits and innovative visual essays have graced the covers and pages of many other magazines, including Life, Esquire, Fortune, GQ, Geo, Sports Illustrated, ESPN and The New York Times Magazine. He has also photographed major advertising campaigns for such clients such as American Express, Benson & Hedges, Dewar's, Ford, Guinness, Marlboro, Merrill Lynch, Nike, Pfizer, Reebok and United Technologies. His private portrait commissions include a lithographic print of New York Mayor Ed Koch, which was the first photographic portrait for City Hall in New York City, and large-scale portraits of noted authors and actors, now on display at the National Arts Club.