Completed and interview on campus. Mostly behavioral questions and going over resume. There were no interviews after this. It took them longer to respond than they said it would, but it was only by a week or two. The interviewer was friendly and made it seem very casual.

I spoke to 3M at my school's career fair and was contacted close to two months later for an interview. I don't believe that is the standard time frame, I got the impression that they were somewhat disorganized this year. The man interviewing me was nice and somewhat casual compared to other interviews I have had; he stated in the email to dress business casual and that it was not necessary to wear a suit.