A total of 2635 skeletons recovered from different sites in England was examined for the presence of osteoarthritis (OA); 206 were from pre-medieval sites, 1453 from medieval sites and 976 from post-medieval sites. Where OA was considered to be present in a joint, the site was noted and for each time period the total number of anatomical sites with the condition was determined and the number of major sites with OA (10 in number) was expressed as a proportion of this total. There were no differences in the distribution of osteoarthritis between the pre-medieval and medieval periods but there were between the medieval and post-medieval periods. In the post-medieval period the proportion of osteoarthritis of the knee increased whereas that of the hip decreased; the proportion of osteoarthritis of the hands also increased whereas that of the wrist decreased. Other data presented indicate that patellofemoral disease is about twice as common as tibio-femoral disease in both medieval and post-medieval periods and that lateral compartment disease is almost as common as medial compartment disease.