Among Donaldson's many appearances at the theater leading roles in All's Well That Ends Well, As You Like It,Homeward Bound, World of Wonders, The Taming of the Shrew, Long Day's Journey Into Night, Much Ado About Nothing, Timon of Athens, To Kill a Mockingbird, Twelfth Night, Who's Afraid of Virginia Woolf?, The Threepenny Opera, and King Lear.
He was last seen at the theater in 2008, appearing in productions of Caesar and Cleopatra, Romeo and Juliet, and Love's Labour's Lost. This season, he was to have played Buckingham in Richard III and Marcus Andronicus in Titus Andronicus.
Among his other credits are a film version of the theater's Long Day's Journey Into Night, for which he won a Genie for Best Supporting Actor. He also was seen in the film The Sweet Hereafter, and starred, with his wife Sheila McCarthey in the television series Emily of New Moon
In addition to his wife, he is survived by two daughters. Details of a funeral and memorial celebration will be announced at a later date.