I was contacted by internal recruiting for a job as a controller in three different divisions within GS. There was a 15 minute phone interview before any actual interview scheduled. It was very enjoyable and the interviewer was very welcoming. This phone interview consists of behavioral questions. You should expect high level questions like why do you want to switch careers, and why the job posting interested you. I had ~20 interviews in total for the three different divisions. In general, it's reasonable to expect at least 6-7 interviews per division. The interviewers range from associates to VPs and MDs. The questions they ask depend on the division you're interviewing for, the rank of the interviewer, and your job duties. Behavioral questions are expected and there are some technical questions. It wouldn't be unreasonable to expect a couple of brain teasers but this really depends on the position you're interviewing for. For controllers, you should expect to know how to DCF things, calculate P&L, basic valuation modelling, and everything you learned in your finance classes at school. You're called for a second round of interviews if you're selected. The process is similar and there may be more technical questions.