3 rounds- One of the most challenging interviews I have faced. It started with first technical round with the interviewer asking statistical theory questions like liner, logistic etc , later she asked me SAS queries and checked my coding skills by giving me a data set. Second round was person asking me Maths and general aptitude questions- but he asked me not to use pen and paper and solve them mentally so that was quite challenging. In addition to that both First and second interviewer were telling me things like "Oh god u can't do this? Oh c mon this should not take this much time etc." Guess they wanted to see the ability to perform under pressure/ add to the challenge. Third Round was with the team director- was more like a general catch up and HR type questions- Tell about yourself? Why BCG? He also explained about the things to expect and kind of work they do. In the end he gave me a guesstimate question.