The process was a bit lengthy to start with and it might have been the holidays but I'm not really sure. It will start with a phone screen from the HR Manager and once you've passed, they will schedule an interview. I actually interviewed with 2 supervisors and the HR Manager which took about 3 hours total. HR Manager is there to verify your skills and experience and the Supervisors are there to question how well you would work with them and to how the department works. The initial interview was pretty straightforward with no surprise questions. The follow up interview involves other people connected to your dept - R&D, Product Managers, etc. They are there to also verify your skills, experience and how well your past experience relates to the current position you're interviewing for.