I applied through an employee referral. I interviewed at MIT
Interview
Most professors will invite you onsite for a talk, then you will speak to each one of their students. Generally the way to get in is to have people like you, not to come off as a "know-it-all".
I applied through other source. I interviewed at MIT
Interview
All day informational interviews with all the lab mates. Took most of two days. Meet with the PI at the end. Gave a talk. In general chill but stressful. Meet lots of good people