I got my interviews from an employee referral. HR contacted me and we set up a time to have a phone interview. They basically told me about the company and what kinds of benefits I would have. Other than that we chatted about various points on my resume. Wasn't anything too informal - just be yourself. From there we set up a time for me to go to PPD for three separate interviews (20 min each) with three supervisors. Each supervisor has a packet of questions that they need to ask, which were obviously put together by HR. On each page they have three different questions they can ask, so they choose one and you answer it. The supervisor takes notes and moves on to the next page. While answering questions you chat about your resume and just get to know one another. Just be your bubbly self - no one wants to work with someone who is awkward in an interview. It was not a difficult interview process at all, as long as you don't get yourself hyped up about it.