Integration testing, it must've been several years ago that I first got to know the concept. Like unit testing, the benefits were and still are quite obvious. When developing I've found a good set of tools to do unit testing, but finding a set of tools to do integration testing has been a constant struggle. I tried using Selenium and WatiN. Creating the little tests with the recorder was pretty neat, but reality struck pretty fast when I experienced first hand how brittle UI integration tests really are. Change something in the UI? You can practically throw away your existing tests and start over. Because the tests were so brittle, the result was hardly usable and very time consuming. Tests were constantly failing just because something changed in the UI, not because there was a bug in the application. Maintaining a suite of UI integration tests was not an option.