I went through 3 phone interviews and 4 in-person interviews which lasted 4 1/2 months from initial phone call to offer. Interviews were similar each time yet each interview was with different departmental leads in which I would be working with (dotted line in the org chart). Interviews were formal so definitely be dressed to impress. They go through TONS of interviews for each opening so find a way to make yourself stand out; I used hand-written 'thank you' notes for each interviewer, personalized business cards, and connected with each interviewer on LinkedIn prior to each interview.