After I submitted my application online, I was contacted by email to set up a phone interview. The phone interview was very casual, and lasted about 30 minutes. It was mostly just chatting with the woman who became my direct supervisor about my schoolwork and interests, and to see if our personalities would mesh. After that I was asked to come to the office for a similarly casual in-person interview. As far as I can tell, the interns are hired individually by the people who will train them.