Attended a firm-wide information session at my university, then applied. Received an email about a phone interview a couple of weeks after applying. After the phone interview, received an email indicating made it to the next round and needed to be in New York the following week. Had the Superday in New York which involved a brief case study (was about an hour and a half) and 4-5 20 minute interviews with different team members. Overall, everyone I met with was extremely professional and genuinely nice - they're interested in knowing how you think and why you're interested in working at Citi. The entire process from attending the information session to getting the offer took about a month.

A thirty-minute phone interview covering a range of questions: some behavioral, some about Citi (the group, your interests, the CEO's name, what their stock is trading at that day, etc.), and some general questions about the markets