They're very interested in how well new employees will fit into the company's culture. The interview process includes a formal interview with two of the three principals, then they'll send you off to have coffee at the local Peet's with a couple of the other employees.

I called the office to follow up on my initial email and city confirmation that my materials has been received. A few days later (a week?) I received a "get to know you" phone call and request to schedule an interview. I met with all the principals to show my work and discuss their work.