The event that helped transform youth culture in the “Mad Men” era was sparked by a spirited conversation one night in early 1967 at Cass Elliott’s house among the singer, Paul McCartney, John and Michelle Phillips and uber-producer Lou Adler.

Rock ‘n’ roll had an image problem, they decided. It wasn’t taken seriously as an art form, unlike jazz. Within weeks, Adler was leading the charge to assemble a festival to showcase the best of the biz. The Monterey Intl. Pop Festival, held June 16-18, 1967, at the Monterey Fairgrounds, proved a landmark gathering that not only rocketed Jimi Hendrix, the Who, Janis Joplin, Otis Redding and other acts to mega-stardom, it also signified the emergence of the counterculture as a social force to be reckoned with.

Among the upcoming events celebrating the fest’s 45th anni, Los Angeles film aficianado org Cinefamily is hosting a June 17 screening of D.A. Pennebaker’s “Monterey Pop” docu that cemented the fest’s place in history after its release in 1968. Adler and Michelle Phillips, who was a key organizer and talent wrangler for the fest, will be on hand for a post-screening Q&A.

“The most important thing that has transported Monterey from generation to generation is simply the iconic musical performances,” Adler said. “And then you consider not only the cultural explosion that was happening at the time. It’s a historic event that is easily identified even by the young people of today.”

The lineup for that gathering reads like a classic rock and pop playlist including Simon and Garfunkel, Lou Rawls, the Animals, the Grateful Dead, the Byrds, Laura Nyro, the Steve Miller Band, Booker T. and the MGs, the Association and of course, Adler’s hitmakers, the Mamas and the Papas.

Adler said the goal was to reflect “the best of everything that on the radio at the time,” which meant sending emissaries to England where they turned up the Who and the Jimi Hendrix Experience. The Beach Boys were on the bill but famously canceled at the last minute. Donovan was supposed to come but got busted for pot and lost his work visa.

Adler said he’s most proud of the fest’s legacy of philanthropy, which continues to the present day. Long before Live Aid et al, all of the major acts donated their services in order to allow proceeds from the fest, the movie and soundtrack album support various charities, including the original Free Clinics in L.A. and San Francisco and, more recently, MusicCares’ MAP Fund that aids musicians battling substance abuse.

“We’re still writing checks,” Adler said.