First interview was basic phone call...the recruiter forgot about me and offered another time...didn't really set a great example but the rest of the process went smoothly.
Second interview was with the hiring manager who was very polite and gave a lot of details around the job, expectations etc.
Third session was the panel interview which was with several different employees. All of them were quite intensive with a lot of follow-up questions around their leadership principles. Don't underestimate this step!