I was referred by a friend who has a job there. I applied online and was contacted for a telephone interview. The telephone interview was quite relaxed and more like an informal chat with a HR guy. Following that I was invited for an interview day at their Abingdon office. The interview day began with me arriving half an hour late after my alarm didn't go off - whoops. I phoned them before arriving, and they were very understanding and told me to still come for the interview. Upon arriving I was introduced to a few people, and then given a programming task to complete. The programming task was fairly trivial and could really have been finished within an hour. As I was given the whole day to do it (more or less - 10am until 4pm with a couple of hours taken for lunch and being shown around), I went overboard with my solution in an attempt to impress. At 4pm I told them that I had finished my solution, and a couple of guys came over to have a look. They played with it for a bit, tried to break it, checked my code, questioned me on various bits of code. Thankfully, despite being probably over-complex, my code didn't fall to bits. Make sure that you check for invalid inputs, as they seemed keen to make sure that it wouldn't crash with an invalid input. After that I gave a short presentation to someone, and then had another chat with the HR guy. He discussed various terms of the contract, and I explained that I had another offer with a deadline.