In recent years much work has been done on both the observational and theoretical side to confirm the place of AGN feedback as an important component of
galaxy formation and evolution. While we are now fairly confident that these feedback processes are necessary to explain the observed properties of
galaxies the true nature of AGN feedback, and in particular the evolutionary sequence from starburst through an AGN phase to quiescence has so far proven
to be very difficult to observe directly. In this talk I will review our current understanding of AGN feedback and its role in galaxy evolution, as well
as present some new results from Spitzer mid-IR spectroscopy of post-starburst galaxies which may directly show the effect of AGN on their surrounding
medium as a function of time.