Barnet-Lab, Gee, Geraghty and Taylor have shown that essentially self dual Galois representations of a totally real field on Q_p-vector spaces that are unramified almost everywhere and de Rham at p are automorphic if they are ?potentially diagonalizable?. In this talk I will explain the objects in this theorem and explain how to reprove this theorem using p-adic automorphic forms of finite slope. Unlike the previous work mentioned above, this new method generalizes to the case of CM fields.