A small panel, including the hiring manager, asked me performance and behavioral questions for about 20 minutes then allowed me to ask questions for as long as I felt necessary. It was very open and there was little pressure to give "right answers." I was invited to apply for the position, so it is likely that the panel had already decided to offer the position to me ahead of time.

Online phone screening with third party recruiting company, lead to in person interview with hiring manager onsite. Process post interview is very long if going for security clearance. Really depends on the hiring manager as they are directly involved in the interviewing process from the get go.