The first round interview lasted approximately 5 hours. The first hour is spent meeting your potential team members. The meeting is structured in a panel setting (i.e. all team members are in the room with you at the same time). The questions are relatively basic--questions you would get in any finance interview. The next 4 hours are spent working on a detailed case study as Luminous wants to make sure you have what it takes to do the job. Approximately halfway through the case study they take you to lunch to give you a chance to relax and get to know a more senior member of the team. After you complete the case study the initial interview is effectively over. They will review your results and get back to you should they be interested in scheduling a second round interview. The second round interview is essentially a meeting with one of the partners. It lasts approximately 45 minutes. Be prepared for more pointed and direct questions. They're not difficult or unexpected, just more detailed and specific.