In 1966, Phillips exhibited at the Royal Academy Summer Exhibition for the first time, started work on "A Humument", and began collaborating with Brian Eno. When Cornelius Cardew founded the Scratch Orchestra, its constitution was drafted in Phillips' garden in Bath (where he had become a teacher at the Bath Academy of Art) and he participated in most of the concerts until he became disillusioned with its politicization. In 1968 he moved to Wolverhampton to teach at Wolverhampton School of Art, and he had a second one-man exhibition, at the Ikon Gallery, Birmingham. He wrote the opera "Irma" in the following year and started the "Terminal Grey" series of paintings.