3 interviews; two phone and then onsite; trivial math problems; the interviewer is pretty nice unlike most people said here; I guess if you know the material, the interviewer is generally really nice and patient

Had an initial phone interview after submitting resume online with some simple brain teasers and "behavioral" questions gauging interest in the job and in the field (i.e. what my interest is in trading, whether I am applying to other positions, etc.)