Salaried professional position. Obtained through headhunter. Had 1 pre-screen phone interview with headhunter, then had 3 phone interviews with various people in BASF HR before being invited to an on-site interview. Spoke with 3 upper level managers in hiring division, interviews were round-robin style, spoke with one manager for an hour, switched rooms to talk with another, etc. There were other potential candidates for same position interviewing that same day, also switching rooms with same managers. Interview was relaxed and casual, they wanted to know what level of expertise/experience you had and how you would be a good fit and bring value immediately to the division. Decision made quickly, within a few weeks of interview, offer made, and salary negotiation with HR began.