I worked as an engineer in big enterprise at 35 hours a week + RTTs - meaning I am working 37.5 hours but I can take more days off. Everything sounded great before I went there and realized there is double standard - employees vs. contractors. If you are a contractor you have no rights and you are expected to work as much as your manager says. In the end I was spending more than 50-55 hours a week and the overtime I did was not paid accordingly. If I wasn't OK with this I'd be let go easily and there are no laws that protect me. I would not be fired, but I will be transferred back to the contracting company who is not obliged to pay me, if I am not working for a client.