I think it pays not to lose your cool in any professional environment. The key (as far as is humanly possible) is to be polite, respectful and easy to work with or for, in any professional context. Bottom line, chances are that you will cross paths with these people again, and the probability increases significantly when you meet people who know other people etc. Case in point. I used to work with a fellow developer who was just an ass. Unhelpful, condescending, backstabbing - just a plain awful human being (good coder but soft skills were a real issue for this jerk). In the last 10 years I've been asked multiple times to provide a reference for this guy via mutual contacts simply because I worked with him in the past - and have refused every time. Politely and legally. It speaks volumes. Lots of doors have closed for him just because he couldn't take the time to act like a decent human being. ...and it costs so much energy to be a dick, why bother burning bridges?