Phone interviews with the hiring managers and recruiter, followed by two on-site interviews. The process was long but well worth the effort -- with each stage, I learned more about the company, product, and teams I'd be working with. Everyone is very smart and approachable, and the questions were well-selected in sussing out whether I have the knowledge and drive to do this role. In the end I didn't receive an offer, but I really enjoyed the conversations... it's a rare opportunity to interact with so many talented individuals who love discussing different aspects of performance marketing.