I was initially contacted via phone directly by the hiring manager. The phone interview lasted about 45 minutes and consisted mainly of general inquiries about my background, experience, strengths and weaknesses. The phone interview was really to get a feeling for my personality and to see if it may be a fit within the department. Since my phone interview went well, I was asked to come in to meet the team in person.
In a matter of days, I was scheduled to visit the office and was told I would be meeting with multiple team members over the course of about 4 hours. Since the AMEX offices are in the World Financial Center, security is extremely tight. It may take up to 20 minutes to get through security as a visitor (ID creation, x-ray machine, bag search etc.) so be prepared to arrive earlier than usual if you interview here.
The AMEX offices are very "corporate". Nothing too fancy, but extremely clean and organized. I was immediately greeted when stepping off the elevator by my first of four interviewers. We stepped into a small conference room and began the process immediately. I met with the hiring manager, the Vice President of the department and two other senior level team members (one after the other). I was asked to look at various reports and tell them what strategy I would implement in each situation. One of the toughest questions I received was "tell me about FIVE of your weaknesses". I was prepared with one or two, but five was a bit of a stumper!
Overall, everyone I met with was extremely nice and personable. The corporate culture at AMEX is very collaborative, but I hear that there are many layers to get through in order to have your ideas taken seriously (that is, if you are in a more junior position). They put a good deal of emphasis on work/life balance and I got the feeling that they really meant it. Although they decided to go with an internal candidate for the position I was going for, I still keep in touch with those I interviewed with and they are keeping me in mind for future openings. Good to know that your resume is not shredded right away if you are not hired for one position.