The kits tested are the Y-PlexTM 5, Y-PlexTM 6, Y-PlexTM 12, Powerplex Y, Y-FilerTM, Multiplex I (MPI), and MPII. Amplification of between 0.5 and 1.0 ng of DNA was performed. The study demonstrates, except for the discrepancies noted, that all primer sets currently available will produce concordant results. Significantly, there was a 100 percent concordance between the typing results obtained from the two most commonly used commercial Y-STR systems, i.e., Powerplex Y and YfilerTM kits. This indicates that results obtained for forensic samples can be compared even when using different amplification kits. In addition, databases constructed using one amplification kit may be used to determine the frequency of a particular haplotype obtained using a different amplification kit. Three discrepancies are explained, accompanied by explanations as to why they do not discount the main conclusion of the study. 2 tables and 11 references