He trained at the Bristol Old Vic and worked as an actor and director for many years in the United Kingdom, finishing as artistic director at the Greenwich Theatre from 1973–75.
He was hired as artistic director at the Stratford Festival in Canada in 1975, where he spent six seasons directing many landmark productions and cultivating new talent.
Such actors as Maggie Smith, Richard Monette, Martha Henry, and Brian Bedford, among others, were prominently featured during his tenure, and many of his Shakespearean, classical, and contemporary productions won widespread acclaim.
When he resigned from Stratford during the 1980 season, exhaustion was cited as the primary reason for his departure. He would later become artistic director at the Grand Theatre in London, Ontario and return to Stratford to direct the Young Company in 1987–88. He was also director general at the Citadel Theatre in Edmonton from 1990–95.
He directed a musical version of Jekyll & Hyde (1997) on Broadway (winning the Drama Desk Award for Outstanding Set Design for his contribution to the scenic design); Long Day’s Journey into Night in London’s West End in 2000; and a stage version of Larry’s Party at Canadian Stage and the National Arts Centre in 2001.
In 2010, Phillips received the Governor General’s Performing Arts Award for Lifetime Artistic Achievement, Canada’s highest honour in the performing arts. Phillips died 25 July 2015 after a prolonged illness.