I go to talk to a Google recruiter at some software exhibition where Google had a booth. Later on he contacted me by email and proposed me a phone interview after I have sent him my resume. Before the interview I got a self evaluation form asking to rate myself on technical knowledge on: Java, python, Perl, build tools, scm systems (perforce, cvs etc.), shell scripting, Linux/WIndows system administration, SQL. The interviewer wanted to find out my general understanding of the software release process (waterfall model, agile etc.) by asking questions like: Assume you have a bugfix release in 1 month, another major release in x months. How would you branch the code? Then he wanted me to code in unix shell. He also asked about my current job.

Very professional process. Every person I interviewed with was very professional. You are give all the information you need to go through this process. It can seem intimidating at first. There are multiple interviews. They explain to you the subject matter of the interviews. They provide material from which you can study. They even personally reach out to you if you do not get the position. Most companies just send an email or ghost you. I would recommend this company to a friend.