Here we consider when the difference of two composition operators is compact on the weighted Dirichlet spaces D α . Specifically we study differences of composition operators on the Dirichlet space D and S 2 , the space of analytic functions whose first derivative is in H 2 , and then use Calderón's complex interpolation to extend the results to the general weighted Dirichlet spaces. As a corollary we consider composition operators induced by linear fractional self-maps of the disk.
MSC:47B33, 46E20, 47B32