It was a three step process that consisted of an initial phone interview followed by set of questions which I assume helped determine if a in-person interview was granted. After the answers were submitted I got a phone call a few weeks later scheduling a real interview!
In terms of people, there were four people involved. One person set-up and conducted the phone interview, another person called to set-up the in-person interview and two different people conducted the in-person interview.
Overall, everyone was clear, professional and respectful. They always sent follow-up emails after a phone call and confirmed dates and times. Although I did not get the job, they called and provided constictive feedback and told me to look out for other opportunties within the organization.