After submitting my application in January, I got an invitation to interview on-site at the FRB in mid-April. There was no intermediate interview (such as a phone screen) at all. Before the interview took place, I was told I was going to interview with two sections I wasn't particularly interested in working for. However, when I walked into the interview I was informed that my interview schedule had changed completely! I was instead going to interview with 4 entirely different sections (all of which I was substantially more interested in). The interview with each section lasted exactly 30 minutes. The first 20 minutes was spent with the Economists, and the remaining 10 minutes was spent with the Research Assistants. There was also a 1-hour lunch "interview" with some Research Assistants. All the interviews with the economists were fairly low key. Most of the 20 minutes was taken up by them describing the work done in section, with a few questions here and there about my resume. I don't remember being asked any technical questions. The interviews with the RAs was even more low key and conversational. I remember talking to them about how they like living in DC. At the end of the day, I ranked the 4 sections according to how interested I was in working with them. Overall, it was an easy interview. Just be ready to discuss what's on your resume, have questions, and be friendly.