  Tidal interactions can play an important role as compact white dwarf (WD)
binaries are driven together by gravitational waves (GWs). This will modify the
strain evolution measured by future space-based GW detectors and impact the
potential outcome of the mergers. Surveys now and in the near future will
generate an unprecedented population of detached WD binaries to constrain tidal
interactions. Motivated by this, I summarize the deviations between a binary
evolving under the influence of only GW emission and a binary that is also
experiencing some degree of tidal locking. I present analytic relations for the
first and second derivative of the orbital period and braking index.
Measurements of these quantities will allow the inference of tidal
interactions, even when the masses of the component WDs are not well
constrained. Finally, I discuss tidal heating and how it can provide
complimentary information.
