Crosby, Stills & Nash (CSN) were a vocal folk rock supergroup made up of American singer-songwriters David Crosby and Stephen Stills and English singer-songwriter Graham Nash. They are also known as Crosby, Stills, Nash & Young (CSNY) when joined by Canadian singer-songwriter Neil Young, who is an occasional fourth member. They are noted for their intricate vocal harmonies, often tumultuous interpersonal relationships, political activism, and lasting influence on American music and culture. Crosby, Stills & Nash were inducted into the Rock and Roll Hall of Fame and all three members were also inducted for their work in other groups (Crosby for the Byrds, Stills for Buffalo Springfield and Nash for the Hollies). Neil Young has also been inducted as a solo artist and as a member of Buffalo Springfield. They have not made a group studio album since the 20th Century, and are inactive as of 2020. Whether or not this break is permanent remains to be seen, as the group has often been inactive for years at a time.