American political activist and founder of the Youth International Party (Yippies), who was known for his successful media events.

Hoffman, who received psychology degrees from both Brandeis University (1959) and the University of California at Berkeley (1960), was active in the American civil-rights movement before turning his energies to organizing the Yippies (1968), who were dedicated to protesting the Vietnam War and the American economic and political system. He gained widespread media attention for his exploits, most notably for his courtroom antics as a defendant in the so-called Chicago Seven trial (1969), in which Hoffman was convicted of crossing state lines with intent to riot at the Democratic Party's national convention in Chicago in 1968; the conviction was later overturned.

After he was arrested on charges of selling cocaine (1973), Hoffman went underground, underwent plastic surgery, assumed the alias Barry Freed, and worked as an environmental activist in New York state. He resurfaced in 1980 and served a year in prison before resuming his environmental efforts. He was the author of such books as Revolution for the Hell of It (1968), Steal This Book (1971), and an autobiography, Soon to Be a Major Motion Picture (1980).