Initial brief interview with the recruiter. Then passed on to the next round of 3 consecutive interviews which took at total of 2 hours. First interviewer was an associate, the 2nd was a senior associate and the 3rd was a manager. the associate was easy to talk to as he was about my age and just went down a list of common interview questions and jotted down my responses. The second one was more behavioral. the last interview with the manager was a conversation and we just talked about our backgrounds. It was also a time for me to ask any questions that I had.
I had another interview for the same company at a different office and was broken into 2 separate interviews. The first was with a partner and the second was a 2 on 1 interview with a manager and partner.