Atmospheric parameters and abundances are given for a sample of 20 red giants observed in the field of 10 open clusters. The clusters have ages between 80Myr and 610Myr. File table5.dat contains the atmospheric parameters; file table6.dat contains the abundances of C, N, and O; and file tablea1.dat contains abundances ratios for 28 species of 22 other elements, i.e., [FeI/H], [FeII/H], [AlI/Fe], [BaII/Fe], [CaI/Fe], [CeII/Fe], [CoI/Fe], [CrI/Fe], [CrII/Fe], [CuI/Fe], [EuII/Fe], [LaII/Fe], [MgI/Fe], [NaI/Fe], [NiI/Fe], [ScI/Fe], [ScII/Fe], [SI/Fe], [SiI/Fe], [SiII/Fe], [SrI/Fe], [TiI/Fe], [TiII/Fe], [VI/Fe], [YII/Fe], [ZnI/Fe], [ZrI/Fe], and [ZrII/Fe]. Parameters and abundances were determined in a model atmosphere analysis of high-resolution spectra obtained with the FIES instrument at the Nordic Optical Telescope. Abundances of C, N, and O were computed using spectrum synthesis. The atmospheric parameters and remaining abundances were determined using equivalent widths. The individual Al and Na abundances as given in tablea1.dat have been corrected for nonlocal thermodynamic equilibrium (non-LTE) effects. <P />(4 data files).