I was recruited out of a career fair at my school. My resume was passed along, I was emailed in less than two weeks to set up a phone interview. Interviewer told me that there were 20 people interviewed on the phone. I found out that I was getting an on-site interview by the end of the week. The on-site interview was 2-3 weeks later. I presented a 50 minute presentation on my thesis work. I had several interviews with teams of one or two all day. All questions were behavioral yet technical at the same time. They want to hire someone that can work with people at all levels, outgoing, overachieving, intelligent, ethical, moral, and personable. They will ask you the same question 2-3 times that day so you can change answer or clarify later. I met mostly with other research scientists and once with HR. By the way, THE OTHER THREE FINAL CANDIDATES WERE THERE ON THE SAME DAY. You see them, have lunch, stay at the same hotel, have the HR benefits presentation with them. Don't get freaked out, be genial, not personal with other candidates. At the end of the day, they told us that we would know if we had the job or not the next day. The next day, I received an email to schedule a follow up phone interview with my would-be line manager about mostly technical questions and why I wanted to work for an oil company. The next day, he called me, told me I had the job, explained the benefits, and had 10 days to decide. I accepted. It was an EXTREMELY fair process. BP's travel agency works with you to create a seamless trip and they put you up in the best accommodations, refund all expenses you incur.