I got an invite for the first round and it is the Problem Solving Test and Group Interview workshop about 2 weeks after the resume deadline. PST I've heard that during this round, the PST is what they are primarily judging you on. There is an unknown cut off score (rumors about it range from 60-70%) for a pretty challenging test 26 questions in 60 minutes. They have 3 practice tests online with answer keys. Some of the questions are like GMAT integrated reasoning questions but they're not exactly the same. Group interview There's a lot of variability among the group interviews depending on your interviewer. My first one would ask the same question to all of us but would rotate the order in which he asked us questions. My second one asked questions but would pick a random person from the group to answer the question and then ask if any of the rest of us had questions. I've heard that the group interview part is just to make sure that you can work on teams (so it's good to add on to other people's answers and synthesize what's been said). I'm not sure how much the group interview part counts especially since for my second one: half of us got math questions, the other half got strategy questions so I'd imagine it's mainly to give people who move onto the second round feedback. Generally, it was a very organized and structured experience. I really appreciate how quick the turnaround time was- I found out two days after my test that I didn't make it to the next round.