Ample evidence indicates that the evolution of supermassive black holes and their host galaxies is connected, but the physical processes driving this link remain uncertain. The role of galaxy mergers is a matter of particularly active debate, and these events have additional significance as the precursors of black hole binary inspiral and merger. Gravitational wave emission from these binaries may be detected in coming years with pulsar timing arrays or a space-based interferometer. Moreover, asymmetry in the gravitational waves produces a “recoil kick”, which can eject the black hole from its host. I will review recent progress in characterizing the signatures of black holes in merging galaxies, using numerical models combined with the growing samples of single and dual active black holes in mergers. I’ll describe the potential for this approach to provide an unbiased picture of black hole/galaxy co-evolution and to constrain the black hole merger rate. I will conclude by discussing results from simulations that predict promising avenues for finding a population of recoiling black holes in current and future surveys.