Interviewed with BCG as part of on campus recruiting. Did my first round interviews at the Boston Office, met with two consultants, two standard case interviews that started first a little bit with behavioral (leadership experience, team work) from my resume, then a case with each of them. One of the cases involved looking for graphs, but you have to ask for them, so if you feel that you need data to solve the case, be sure to ask. Second round interview in the DC office (your rank top 3 preferred office locations, they fly you to one of them). I had heard that BCG case interviews tended to be very structured with graphs and diagrams, but I got one very open-ended case that surprised me.