Music critics and fans look back at the 30-year career of progressive rockers Pink Floyd, famed for their hugely successful concept albums and elaborate live shows. Founded in 1965, the band originally consisted of students Syd Barrett, Nick Mason, Roger Waters, and Richard Wright. They first gained popularity performing in London's underground music scene during the late 1960s, and under Barrett's creative leadership they released two charting singles and a successful debut album. David Gilmour joined as a fifth member in December 1967, and Barrett left the band in April 1968 due to his deteriorating mental health. After Barrett's departure, Waters became their primary songwriter and lyricist. Pink Floyd achieved critical and commercial success with the concept albums The Dark Side of the Moon (1973), Wish You Were Here (1975), Animals (1977), The Wall (1979) and The Final Cut (1983).