Started with a basic half hour phone interview and was then asked back to a hiring day at their Mountain View campus. They flew me out and had me stay overnight in a nearby hotel. The next day I had three separate one on one half hour interviews at the beginning of the day. Later all the potential new hires that were doing the same thing as me got a tour of the campus and were given a presentation about benefits and what it's like to work at Google. Then waited an excruciating three weeks for their final decision.