In 1965, he returned to Montreal and joined Les Grands Ballets Canadiens as co-artistic director and resident choreographer. He added many diverse works to the company's repertoire, including La Fille mal gard_e, Danses concertantes, Symphony of Psalms, Libert_ temp_r_e, La Scouine, and The Seven Deadly Sins. His Nutcracker has been presented by the company each year since 1964; another notable work was his avant-garde rock ballet of The Who's Tommy in 1970.

Nault remained resident choreographer of Les Grands Ballets Canadiens while serving as choreographer and ballet master at l'ê_cole sup_rieure de danse du Qu_bec. He also choreographed numerous works for American Ballet Theatre, Alberta Ballet, Atlanta Ballet, Ballet Federation of the Philippines, Delta Festival Ballet, Joffrey Ballet, National Ballet of Korea and Washington Ballet. From 1978 to 1981 he was guest choreographer and, from 1981 to 1982, artistic director of The Colorado Ballet.

He received many Canadian awards, including the Centennial Medal in 1967, the Order of Canada in 1977 and the Governor General's awards for the performing arts in 2000. In 1984 he received the Prix Denise-Pelletier, a lifetime achievement award; in 1990 he was accepted as a Chevalier de l'Ordre national du Qu_bec and was named Choreographer Emeritus of Les Grands Ballets Canadiens. In 1976, he won the prize for choreography at the 7th International Ballet Competition in Varna, Bulgaria for his ballet Incoh_rence.

Nault died in Montreal on December 26 from Parkinson's disease.