Phone-screen interview was standard. Asked questions regarding what AdRoll does, what is retargeting, what your current job is like and if I had any questions myself. Be confident and do your research and you can get past this round.
Made it to the second round where I came into the San Francisco office to meet with the Delight team. This process took two hours and I met with four different individuals who asked all sorts of questions. For the second round, be prepared to talk in depth about your current/most recent job, retargeting, where you see the online advertising industry going, and competitors. I was asked several brain teaser questions as well (If I gave you a brick what would you do with it? If you found $5000 what would you do with it? You're the CEO of a professional sports team, how do you improve? etc.)
Made it to the third final round where they ask you to prepare a 20 minute Powerpoint presentation about something you're passionate about and how it relates to career goals. Before your presentation, you will meet with the heads of the delight team for final interview questions.
Great company, cool people, great product. I didn't end up getting the offer, but this company is highly competitive. Tech industry experience helps, especially in customer service. Good luck guys, they're growing and hiring!