A quarter of the Universe is composed of dark matter, but the particle
identity of dark matter remains a deep mystery. I will review recent
progress in resolving this puzzle, focusing on several well-motivated
classes of dark matter candidates, including WIMPs and related
possibilities. I will discuss the theoretical motivations for these
candidates, their diverse implications at the interface of particle
physics, astroparticle physics, and cosmology, and the prospects for
identifying dark matter in the coming years.
