The interview process for me went very quickly. The whole process took approximately 10 days from the first phone interview with the HR rep to when I officially accepted an offer.
Part 1: HR phone interview. Here the representative and I spoke for about 30-45 minutes about my skills/background, aspirations and the expectations of the role.
Part 2: In person 1:1 interview with the hiring Finance manager. This part flowed like a standard interview session. We met for about an hour and again discussed my background/skill set and the expectations of the role.
Part 3: I came into the office again for the business case portion of the interview. They gave me about an hour to prepare my answers for 4 different sample questions. You could present them with how you felt most comfortable, white board, Excel, PPT, etc. I presented my analysis and answered questions for the direct hiring Finance manager, another Finance manager and a Business Controller. This was more of a discussion but they were looking for key practical attributes that would identify you as a good candidate for the role.
Part 4: I had a brief 20-30 minute conversation/interview with the Finance Director. I felt this last step was basically to "feel me out" and learn a little about me.
I received an offer, negotiated a bit and accepted within about 2 days time.