I was offered coffee, it was a very informal interview. The interviewer asked me how I knew the agency. We chatted a little bit, then he asked to show him a few projects from my portfolio, and speak about them. He talked a little bit about the agency's work, answered my questions and walked me to the door.

Typically you would meet with one of the Artistic Directors and if things goes well can also get to meet one of the Partners/other senior team members for round 2. They ask you about your profile, your past experiences and portfolio. Pretty classic/casual conversation, if there is an open position they would be looking for some specific assets but nonetheless it is also about being a good fit for the team as a whole.