NB: I am not currently advising as I am on sabbatical. But the below information may still be of use to students in joint math+cs programs at McGill.

I am one of the departmental advisors for the department of Mathematics and Statistics. I advise for students registered in or considering one of McGill's mathematics/statistics and computer science programs. These programs are (as of Fall 2019):

Note: unfortunately, one thing I can't do is override course caps or open up space in courses that are already full. The Faculty of Science information on course registration problems has information about the procedure for students having difficulty enrolling in courses (the procedures in Computer Science and in Mathematics/Statistics are different).

I am slowly working on making program templates for students in various programs. This is rather tricky because students enter with different backgrounds, so a one-size-fits-all approach is tricky; also because the programs change from year to year (the below templates were up to date as of Fall 2019).

  1. Q: Can the same course count toward both my major and minor/toward two different major concentrations.

    A: In the Faculty of Arts, the answer is no; see this page, which states that "no course may fulfill the requirements for more than one program or concentration requirement." In the Faculty of Science, there is not a general policy; decisions are made on a case-by-case basis.
    One specific case which arises reasonably often relates to Math 222. The department of mathematics and statistics allows Math 222 to be used to count toward both the Major in Mathematics and the Minor in Computer Science. However, students should also obtain approval for this from the department of computer science.