I just implemented the async pattern in a wcf service, when i received the error message: You are not in a unit of work. I knew I had this message before but didn't know exactly what I did back then. So I did some experimenting and just called the UnitOfWork.Start(). This solved the issue. However now I am wondering..is this a good solution or not? What consequences will it have? Will it be removed when the thread stops. What happens behind the scene? A unitOfWork, Nhibernate session is created and will be gone whenever I am done with the thread?