Initial phone screen (~30min) with hiring manager followed by a full-day onsite interview 2 weeks later. The day consisted of several 30-60minute interviews (one-on-one or group) with a wide variety of people ranging from Co-op scientists/engineers to Director-level people. I also presented a 30-minute scientific talk to around 15 people. I didn't get an offer as they went with an internal candidate instead. Two months later, the hiring manager passed my resume to another group that brought me in for another, shorter interview (4 hours). My skills were far less relevant to this position and I didn't get that one either. My impression of the company was great and I easily would've accepted an offer from either group.