I had four individual interviews total, in two rounds. The first round occurred on campus with two members of the marketing team who were around the manager level. The second round was held at the London HQ and was conducted by two heads of different marketing departments - product and general marketing. I really enjoyed my experience with all four interviewers and only declined the offer because I received an offer in big tech, an area I was more interested in that financial services. The decision was made even harder because friends who had worked at AmEx all said it was a great work environment.