Metalorganic chemical vapor deposition (MOCVD) of high temperature superconducting materials has been shown to be feasible, and films deposited to date on flat substrates have electrical properties comparable to the best reported results. However, to take advantage of MOCVD to coat odd shapes, such as the inside of rf cavities, requires innovative techniques. This is a proposal to test the feasibility of one such technique, using MOCVD for production of a seed crystal layer deposited slowly, one atomic layer at a time, on a non-planar substrate. The bulk of the film can then be deposited at high rates, which should produce high quality yttrium-barium-copper-oxide films with excellent crystal orientation and surface quality. As a test article of practical importance, we propose to coat the inside of a hollow cylindrical rf cavity. Radio frequency characterization of the film deposited on a flat surface will be performed in Phase I.