The St. Lawrence String Quartet may be Canada’s best-known international chamber music ensemble. Certainly no other group has done as much to promote Canadian composers as the Stanford-based foursome. But when the group’s cellist decided to step aside last year, the St. Lawrence faced the decision that every string quartet dreads most – how to replace a musician, a partner, and a friend. First decision for the remaining members: should Canadian citizenship continue to be a requirement for admission?