  The environment of a binary star system may contain two circumstellar disks,
one orbiting each of the stars, and a circumbinary disk orbiting about the
entire binary. The disk structure and evolution are modified by the presence of
the binary. Resonances emit waves and open disk gaps. The binary's total mass
and mass ratio as well as orbital elements can be modified by the disks.
Signatures of these interactions provide observational tests of the dynamical
models. The interaction of young planets with protoplanetary disks circularizes
the orbits of Jupiter-mass planets and may produce much more massive extrasolar
planets on eccentric orbits.
