The preparation of YBa2 Cu3 07−x high critical temperature superconducting thin films is reviewed. Thin films have been grown by many techniques, including sputtering, electron beam evaporation, laser ablation, spray pyrolysis, molecular‐beam and epitaxy (MBE). Stoichiometric films with high Tc and Jc have been obtained using each of these methods. The choice of substrate significantly affects the superconducting properties, and among the numerous substrates studied MgO, ZrO,2 and SrTiO3 yield best results. This review outlines the various deposition techniques, the effect of postdeposition annealing and the subsequent film–substrate interactions.