I am an APD and initially applied to the Insight program. Was not selected for the Insight, but they invited me for the first-round interview in the fall. First round at McKinsey is a 1-hour problem-solving test (PST), with 26 multiple choice questions testing quantitative or qualitative understanding of a business case (usually there are 3 cases in one test). The main difficulty is the time limit. I found useful to read questions first, and then skim the discussion before for relevant information - saves a lot of time. McKinsey website has 3 practice tests, and a few more can be found on the internet - practice them beforehand and you'll likely do well (I was getting 21 out of 26 on my practice tests). PST is followed by 2 one-hour breakout sessions -we were divided into groups of 4 and moderated by a McKinsey Associate. It was a fun exercise, and quite useful. They say it's not evaluative, but opinions differ. A couple of days after the 1st round I got an email saying that I passed. One nice thing about McKinsey recruiting is the amount of feedback they give. I was connected with two consultants who gave me feedback on my performance and answered my questions. Second round was about a week later, also in NY office, and consisted of 2 1-hour interviews with an Associate and an Engagement Manager. First 5 mins - introduction, then 15 mins of personal experience (tell me about a time you had to lead a team etc.). They ask very detailed questions about each situation. Then ~40 min case - very structured and with a lot of exhibits/ calculations. I thought that I didn't do a perfect job on one of the cases, but later got a call saying that I passed, and more feedback. Final round was in NJ office - 3 one-hour interviews with principals scheduled throughout the day. Structure is the same as 2nd round. Cases were actually less math-heavy. All PE questions were the same - most challenging leadership situation. So prepare different stories. I felt that I did not perform consistently well during these interviews, and a few days later they called and said I didn't get an offer. It was still a very useful experience.