The first interview was a 30 minute campus interview, since I applied through career services. The interview was all behavoral, just asking why Mercer, why consulting, and then a ton of time for questions. The second round was at their offices and consisted of 4 back to back 30 minute interviews with the analysts and associates. The interviews just ran through your resume, asked you to talk about it, and then just asked what were your strengths, weaknesses, and why Mercer. No technical question or case problems, just purely get to know you and behavioral questions. Heard back a week later but did not receive an offer.