I applied online. The process took 3 weeks. I interviewed at Quorum (Washington, DC) in Mar 2016
Interview
Three interviews and a writing sample.
First interview was very informational over coffee, learning a lot about Quorum and making sure the mission of the company was a good fit. Second interview was over dinner, and more about making sure that the culture was a good fit. The third round was with the co-founder (which was cool because it's still such a small company), and again more informational to ensure that Quorum was a really good fit. The team went way out of their way to schedule when and where it was convenient for me, and the interview process went quite quickly (2 weeks for interviews, and extra week for my writing sample).
Throughout the process, the whole team was very transparent, so I never felt like I was wasting my time and could stay enthusiastic and excited about Quorum. After all three interviews, they asked me to submit a writing sample. I got access to the product, played around with the features a little, and then suggested 3-5 ideas of interesting blog posts that I could write using the data in Quorum. They chose one, and then I wrote a 500 word blog post as my sample. There was a bit of a stressful wait after submitting the blog post, but only because feedback had been so quick elsewhere throughout the process.
I was impressed throughout the process that everyone I was interviewing with didn't strike me as sales people -- they acted like policy nerds who had happened to have found a better way to do policy. That was very reassuring to me and a large deciding factor in deciding to join the team.