I will present the theoretical motivations for dark photons, vector bosons arising from a new U(1) gauge symmetry that kinetically mix with the photon. Such particles appear in a number of extensions of the Standard Model and can also be motivated from a purely effective field theory perspective as they provide one of the few portals to a dark sector. Such states have also found motivation in their ability to help explain astrophysical and terrestrial anomalies, such as the discrepant anomalous magnetic moment of the muon, and may also mediate interactions to light dark matter.