I met their recruiter at the career fair, asked a couple questions about their stack and gave them a resume. A couple days later I get an email invite to an on-campus interview which turned out to be 30 minutes of coding and 30 minutes of discussing my answers afterwards. I wrote sub-optimal solutions for most of the problems because I don't practice tech interviews much, and I failed the SQL question because I've never gone beyond SQLite, but I was able to talk through the logic behind my answers and what I should have done for SQL, so I received on on-site invitation. On site was from 12-4 on a Friday, they booked flights for me that morning and evening. They start with lunch with a couple employees and 2-3 interviewees, then they had three technical interviews and a behavioral, with a little behavioral mixed into the techs. In just about all the problems I didn't remember the names of key data structures, but I talked through my approach and the design tradeoffs that would need to be made, which they seemed to really like. I'm bothering to write this review because I think Blackstone does tech interviews right. Every step of the way I felt that they were testing my thought processes and capabilities, not the "learn the questions" variety of tech screening you usually see. I ultimately took an offer from elsewhere that fit my short term goals better, but I'm definitely applying to BX again next Summer and I have nothing negative to say.