Critics have praised his "elegant lyric baritone voice" and "singularly remarkable interpretive skills" in appearances with virtually every major North American orchestra, including the New York Philharmonic, the Boston Symphony, the Cleveland Orchestra, the Philadelphia Orchestra, the Los Angeles Philharmonic and the San Francisco Symphony.

He has also established a presence in Europe, with appearances in centers such as London, Berlin, Barcelona, Paris, and Prague. He has worked with such conductors as Herbert Blomstedt, Pierre Boulez, Raphael Frühbeck de Burgos, Sir Andrew Davis, Charles Dutoit, Neeme Jarvi, Jesus Lopez-Cobos, Kurt Masur, Sir Roger Norrington, Hellmuth Rilling and the late Robert Shaw and Sergiu Commissiona.

After preliminary schooling at the Universities of Guelph and Western Ontario in Canada, Mr. McMillan studied at the Britten-Pears School in England, and attained a Master's Degree at the Juilliard School in New York. His primary focus has always been the oratorio and orchestral repertoire, and his vocal flexibility and scholarly musicianship have afforded him a broad range of styles and periods - from Monteverdi and Bach to Britten and Penderecki.

He has also taken an active role in the creative process, having had several contemporary works written expressly for him, such as the title role in Sir Peter Maxwell Davies' oratorio, Job, which he premiered in Canada, Britain and Israel. He also sang the Canadian premiere of Songs of Milarepa by Philip Glass.

Despite an unfortunate farming accident 30 years ago that left him a partial paraplegic, he has had the opportunity to perform a number of operatic roles in concert/semi-staged performances. Mr. McMillan is a pre-eminent recitalist. He has been described as an "outstanding Schubertian" whose "voice of glowing freshness and beauty is at the service of an intelligent, lively and distinctive personality."

Professor McMillan joined the faculty of the James Madison University School of Music in 2009.