  Gaseous disks have been proposed as a mechanism for facilitating mergers of
binary black holes. We explore circumbinary disk systems to determine the
evolution of the central binary. To do so, we perform 3D, hydrodynamic, locally
isothermal simulations of circumbinary disks on a Cartesian grid. We focus on
binaries of equal mass ratios on fixed circular orbits. To investigate the
orbital evolution of the binary, we examine the various torques exerted on the
system. For the case where the disk plane and binary orbital plane are aligned,
we find that the total torque is positive so that the semi-major axis of the
binary increases. For the misaligned case, we run simulations with the binary
orbital plane and disk midplane misaligned by 45\degree and find the same
results - the binary grows. The timescale for the circumbinary disk to realign
to the plane of the binary is consistent with the global viscous timescale of
the disk.
