First a behavioral interview via the phone. Easy enough, very friendly! That's followed by an interview at their office. Met with four different interviewers - mix of consultants and managers.

Had a brief phone call with the onsite recruiter, after which I was invited to an assessment centre. Shortly after the Assessment Centre I was invited back for an interview with two managers in the London Office. After finishing the interview I got an offer later that day. Very good process and nice people to interview with. Make sure to prepare the micro teach for the assessment centre, and make sure practice it multiple times before the day, 50% of people in my assessment centre pretty much excluded themselves just because of poor presentations.