He was hired as artistic director at the Stratford Festival in Canada in 1975, where he spent six seasons directing many productions and cultivating new talent.

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.

[5][6][7][8] In a review of Phillips' 1977 Stratford production of Richard III with Bedford in the title role, The Globe and Mail theatre critic John Fraser wrote: "The production Phillips has mounted is stunning, crackling with nuances and details that are spellbinding, while radiating an over-all economy of dramatic management that demands an intense involvement from any audience".

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.

Its creators Susan Coyne and Martha Burns had both been directed and mentored by Phillips earlier in their careers, and wanted to capture some of his technique coaching McKinney, a Shakespeare novice.