I was contacted after participating in the Google Code Jam. The initial screening interview was conducted by somebody who was clearly not technical, and that was probably the only poor interview experience throughout the process. I was pressed to make a decision on location during that initial interview, which was a bit strange, since I would be moving from my home country to whichever location I picked. The staff running the hiring process from then were always efficient and accomodating. The initial phone screen process went quicker than I anticipated, with about an interview a week for around 4 or 5 weeks, and on-site interviews not long after that. The interviews were all of a technical nature, with almost zero fluff. I found it hard to ask questions of the interviewers, because it seemed strange asking questions about the culture of the company after purely technical questions coming my way. All of the interviewers were very proficient and friendly, and even when I got things blatantly wrong I was made to feel good about the next questions coming up -- certainly a confidence booster. The process was unfortunately ended sooner than it should have because of a hiring freeze. I'd suggest anyone who thinks they might want to work for Google go through the process, even if you don't think you're up to scratch, there is no loss of confidence even if you're turned down! Because the interviews are so highly technical, be sure to have good programming theory and Unix knowledge. The interviews are weighted to your strengths, so be honest in your self assessments!

HR round after applying, then coding screening round, if passes, then final round which consists of four coding round or three coding and one design round. Problem difficulty medium to hard.