I was referred by an existing employee, otherwise I do not think I would have gotten a call back. There was an initial phone screener with the HR person, then a follow up phone interview with my potential manager. After that I was invited to an in-person interview that was four hours without breaks, with four different interviewers - two peers, two more senior. In each interview, the interviewer clearly set up that they would type while they talked to me and that there were some pretty specific rules they had to follow and questions they had to ask. The interviews felt stiff and formal as a result, particularly because despite assurances there was no "right" answer, it often felt as if I'd answered it wrong. Had heard about Google's hiring practices like this, but generally left that day feeling really defeated by questions that felt irrelevant to my potential rolee. Was not asked into final round to make a presentation.