Glass composed some of the most notable late twentieth century music, and effectively reinvented opera. He studied with Milhaud in New York and Boulanger in Paris, where he met Serra, later helping him erect his sculptures; back in New York, they ran a removal company with Reich (a former fellow-student: as composers, they shared an ensemble). Artist friends included Close, LeWitt and Nauman. Collaborators, mostly friends, included Smith, Anderson, Ginsberg, Reggio, Tharp, Lessing, Childs, and probably most importantly, Wilson. He said Shankar (for opening his mind to non-western music) and Lessing (for her intellect) were his most valued friends.