I applied online. The process took 2+ months. I interviewed at Digitas (Boston, MA).
I had an interview with four people (one at a time), all creatives (this after an initial phone interview with HR). Two were Art Directors, two were copywriters. They mostly let me talk and explain my portfolio. They really liked that I brought a print version of my portfolio and a copy of my resume for them to take with them after the interview. It's very intense, because I got about 40 minutes with each person, so after 4 people I was exhausted.
It was an internship, so I didn't argue the salary.
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