Detection of gamma rays from the annihilation or decay of dark matter particles is a promising method for identifying dark matter, understanding its intrinsic properties, and mapping its distribution in the universe. I will review recent results from the Fermi Gamma-ray Space Telescope and other experiments and discuss the constraints these place on particle dark matter models. I will also present a novel approach to extracting a dark matter signal from Fermi gamma-ray observations using the energy-dependence of anisotropies in a sky map of the diffuse emission. The sensitivity of this technique and its prospects for robustly identifying a dark matter signal in Fermi data will be discussed.