1st interview was over the phone and took roughly 10-15 minutes asking mostly very general situational questions. 3 days later, I was called to scheduled an interview that took roughly 4 hours. They had me sit with 2 different employees for 10 min each and watch them do their jobs. Then, after about an hour and a half of situational & behavioral questions with 2 supervisors I then had to do a series of computer tests (some timed), consisting of simple math, "what would you do?" type questions, a typing test, a few mock phone calls, (mainly to test listening comprehension and sales ability, even though my particular job has nothing to do with sales), then about 5 days later they called me back in for an hour to meet with a manager who had a few more questions for me, (but it was less rigid and more conversational), and then they had me meet the person who would be my direct supervisor and made me an offer.
There is also a very involved background check (takes about 2 weeks), due to the nature of the job and having access to people's private information.