Initially a phone call of about 20 min with the manager of the team. Then 3 rounds of interviews spaced out over quite long period of time (approx 2 months). In the first interview I met the team and manager. I also presented a short presentation. In the 2nd interview I met with the head of the department when he was in London (he was based in Berlin) and then the 3rd interview was a 20 min Skype call with senior management in California.