The all-sky ACO (Abell, Corwin and Olowin 1989, ApJS, 70, 1) Catalog of 4073 rich clusters of galaxies and 1175 southern poor or distant S-clusters has been searched for published redshifts. Data for 1059 of them were found and classified into various quality classes, e.g. to reduce the problem of foreground contamination of redshifts. Taking the ACO selection criteria for redshifts, a total of 992 entries remain, 21 percent more than ACO. Redshifts for rich clusters are now virtually complete out to a redshift z of 0.05 in the north and of 0.04 in the south. In the north, the magnitude-redshift (m_10 - z) relation agrees with that of Kalinkov et al. (1985, Astr. Nachr., 306, 283). For the southern rich clusters, minor adjustments to the m_10 - z relation of ACO are suggested, while for the S-clusters the redshifts are about 30 percent lower than estimated. This table was created by the HEASARC in May 2010 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/165A">CDS Catalog VII/165A</a> file catalog.dat. This is a service provided by NASA HEASARC .