Chester Leo "Chet" Helms, often called the father of San Francisco's 1967 "Summer of Love," was a music promoter and a counterculture figure in San Francisco during its hippie period in the mid- to-late 1960s.

The Summer of Love was a major social phenomenon that occurred in San Francisco during the summer of 1967. As many as 100,000 people, mostly young people, hippies, beatniks, and 1960s counterculture figures, converged in San Francisco's Haight-Ashbury district and Golden Gate Park. More broadly, the Summer of Love encompassed hippie culture, spiritual awakening, hallucinogenic drugs, anti-war sentiment, and free love throughout the West Coast of the United States, and as far away as New York City. An episode of the PBS documentary series American Experience referred to the Summer of Love as "the largest migration of young people in the history of America".