It's a multi-step process. An initial phone interview to screen out the obviously unqualified. A second interview is held on-site and is Technical in nature. It involves both a written and verbal evaluation. If you pass this stage you're pretty much a shoe-in, but there is one final interview with immediate manager of the position that looks mostly to verify (in-person) whether you're a good fit personality-wise with the existing team. The manager also typically drills deeper into your resume work history to gauge whether you're being honest about what you've written down. There is a fourth (optional to management) interview where you may be asked to interview with one or more team members from other organizations in the company. They're interview styles vary.