Pros
Three is a fantastic company to work for. You feel part of something special, a revolution or evolution perhaps in mobile. Regular open bars provide a platform for company updates that are both enjoyable and informative. The behaviours that Three staff live by are in line with the behaviours I live by outside of work so it's a great fit for me. A friendly chat with the CEO in the lift is not uncommon and everyone no matter what level is very approachable. What's great about Three is that you are encouraged to challenge the status quo. If you can do it better, take responsibility and do it! There's plenty of opportunity for self-promotion. The social life is pretty good too!
Cons
Too many meetings! At Three was have meetings about meetings! Also priorities can change here, very very fast. So something you may have as top of your priority list one day may sink to the bottom the next, it can be frustrating. Honestly though I haven't really got anything bad to say. I have found my home here.