Lots of interviewers. Many were very tough on me. They asked questions very quickly and it was difficult for me to slow myself down to think about the questions extra.

Initial contact was through the corporate human resources department in Illinois. They conducted a telephone interview that appeared to be based upon a script of questions, such as "describe a situation where you were faced with unexpected obstacles in completing your task. How did you handle it and what was the outcome?" After my responses to those questions were reviewed and (apparently) approved, I was scheduled for an in-person interview with two people. That interview focused more on my actual work experience, education, skills, etc. The interviewers were pleasant and created a relaxed atmosphere. Overall, a good interviewing experience. One tip: the very first question I was asked at the in-person interview was "what did you do to prepare for this interview?" I think they reacted very favorably when I was able to list 5-6 things I had done to research the company, the interviewers, and possible issues I might be facing in the position.