I applied online. The process took 2 weeks. I interviewed at National Analysts (Philadelphia, PA)
Interview
Very simple hiring process, main thing is the full day of interviews. Really just case interviews with 2 senior people + a bunch of "fit" questions. Great culture and great place to work (good hours, can have a lot of independence based on the group you're in). Make sure you know a little about market research beforehand.
Interview questions [1]
Question 1
Case interview-style question. Can't reveal b/c would break anonymity ("How many ping pong balls in an airplane?" kind of thing + more notes on methodology)