The initial stages of growth of copper,nickel, and cobalt,deposited in ultrahigh vacuum onto a clean (111) silversingle-crystalfilm have been studied by reflection high-energy electron diffraction in situ. Oriented nuclei and single-crystalfilms (with double positioning) were obtained for all substrate temperatures and thicknesses. No signs of a pseudomorphic growth were detected even in the thinnest deposits. The detection limit of the deposits was 0.05 Å. The sticking coefficient of the first metal nuclei on the substrate was determined as a function of substrate temperature. The present results differ considerably from those obtained previously in conventional high vacuum, demonstrating the influence of contaminants in the latter.