In the 1960's there was a core group of artists in San Francisco that came to be known as the "big 5." Of course many artists working at that time did great work but are not as well known. The Big 5 are Rick Griffin, Stanley Mouse, Alton Kelley, Victor Moscoso, and Wes Wilson. In my own collecting preference, Rick Griffin is the most important artist of the group. Mouse and Kelley are inseparable, collaborating on many works, but each have produced an impressive body of individual work. Wes Wilson did the most work for Bill Graham in the Fillmore series of posters, and to many people he epitomizes the psychedelic poster genre. Victor Moscoso's talents emerge most in his underground comix work. His poster work is excellent, but more restrained. His use of color is remarkable. Short bios from Wikipedia are on separate page.s of this website.