Phone interview first. Mostly just to see if you are breathing, have some basic knowledge of computers and customer support. Then a panel interview. This is usually with some direct coworkers, manager or two, and the head honcho. Questions usually crafted to get you to open up and really dive into some technology or other passion that you know a lot about. Some questions trying to gauge effectiveness and ability in dealing with customers. There is usually a practical test at the end if it is felt the candidate might be a good fit. The bottom line is that you are smart, passionate, and able to get things done. It's not always beneficial or necessary to be already well-versed in specific technologies. Sometimes there is an interview with the CEO after the panel interview, sometimes not.