Abstract A process is described for the preparation of superconducting films of “1223” Tl x Ca 2Ba 2Cu 3O y (0.65< x<1.00) via the reaction at 860°C of thallium oxide vapor with spray deposited Ca-Ba-Cu-oxide films containing silver. The thallium oxide vapor reaction was carried out in oxygen in a two-zone reactor which permits the independent control of sample temperature and thallium oxide partial pressure. The films have a textured microstructure exhibiting a preferential orientation of the crystallographic c-axis perpendicular to the surface of the polycrystalline yttria stabilized zirconia substrates. Liquid phase formation induced by the presence of silver is believed to be responsible for the accelerated film growth observed. Films are prepared routinely with T c (0) values of 104–107 K and zero-field critical current densities at 77 K in excess of 20 000 A/cm 2. Values as high as 110 000 A/cm 2 have been measured. The excellent in-field characteristics of the “1223” films are reflected in the behavior of a sample having a zero-field J c value of 105 000 A/cm 2 at 77 K for which a J c>10 000 A/cm 2 was measured at 60 K-2 T with the magnetic field applied parallel to the crystallographic c-axis of the film.