I applied in-person. The process took 6 months. I interviewed at Digitas
Interview
You will meet with so many people in back-to-back meetings who are not necessarily in your discipline. You'll be in one room and people will filter in one after the other over the course of a few hours. Be prepared for an exhausting day. Bring copies of your resume, not everyone who comes in the room has taken the time to learn even your name.
Interview questions [1]
Question 1
People are pretty low key with questions. Just try to ask smart questions and find some common ground to chat about and make an impression. Personal connection counts and so does passion. You might be asked for examples of how you excelled in another job. Pocket anecdotes may help. Not to worry. It's not like a consulting interview--no cases or test questions.
I applied through a recruiter. I interviewed at Digitas (Boston, MA)
Interview
I received an email from an internal recruiter at Digitas. She scheduled a phone screen and then an in-person interview in the Boston office shortly there after where I met the team. I received and offer a few weeks later. The process was pretty laid back and efficient.