I was first contacted by an HR representative to schedule a phone interview. The phone interview was held with an HR representative who went through the typical behavioral questions. Starting with "tell me about yourself", leading into questions such as "tell me about your fundraising experience", "tell me about a tie when you worked with volunteers", "tell me about a time you had difficulty with volunteers", etc.
The questions were pretty standard and not too difficult. I could tell that the woman that interviewed me was reading the questions off of a paper, and could hear her typing about my answers. She wasn't very kind and I didn't think she liked me. But to my surprise, a few days later I was offered a face to face interview.
I had to travel 8 hours for the interview (no expenses are paid for you), and interviewed by two ACS managers in the city where the job was. The interview was very informal, less standardized questions; it felt like more of a conversation than an interview.