First contact was through the phone for a short interview with human resources. They asked generic information about your skills, background, previous employers etc. Then, I was contacted by the supervisor for the position I was applying for to tell me they selected me for an in-person interview. A date was set up and I was given a person to contact to arrange for travel and hotel expenses to be covered. It was indicated to me that I needed to give a 1 hour seminar and would be interviewed by a range of different people with a wide range of different backgrounds.
The day of the interview I was picked up at the hotel and brought to the interview location. After arriving, I met with a person from Human Resources and the supervisor for the position to discuss how the interview will proceed and discussed the scedule for the interview. There was a 1 hour seminar, 5 group interviews with two employees interviewing me (one of which was done remotely with two people on the phone at a different site) that were 30 min each, and a 1 hour interview with the two supervisors directly above the position. In the 30 minute interviews, I was interviewed by other people currently in the same position I was applying for, people below the position in technician roles, technical people in another group that I would be interfacing with, and supervisors.
The questions I was asked were generally split into four categories: Technical Knowledge about the job I was applying for, technical knowledge about past experience and my seminar topic, scenario qeustions designed to test how well I work on my feet, and "HR" questions about teamwork, leadership, conflict resolution, and integrity. The HR questions were fairly generic versions of what you can find online such as "Tell me about a time that you had a conflict with a coworker and how it was resolved?", "Do you prefer to work in teams or on your own?", "Give an example of a time that you exhibited leadership in a role" etc.
After the interview it was about 2 weeks before an offer was made.