Zassenhaus, along with Professors Wacław Kozakiewicz, Charles Fox, Edward Rosenthall, and Phil Wallace, was instrumental in developing the Department's Graduate School.

[2]: 409  McGill's first mathematics Ph.D. was awarded to Joachim Lambek, who obtained his doctorate in 1950 under Zassenhaus's supervision.

[6] In 1963, as public funds came to the university and a larger budget became available, the newly appointment chairman, Edward Rosenthall, concentrated on building a balanced and well-qualified academic team, which could sustain a vigorous graduate program along with the demands made upon the department in a service capacity.

Analysis and algebra became strong elements in the department's program in the late 1960s and the early 1970s, and there was also a lively interest in statistics and in applied mathematics.

[4]: 343  Research in category theory began in 1966, when Lambek decided to promote the subject at McGill.