Periprosthetic joint infections (PJIs) put a high burden on patients and health-care systems. There are currently only limited data on the associated financial costs for a few countries. The overall costs for PJI treatment for Europe are unknown yet. The purpose of this EBJIS project is to determine the health-economic costs of PJI in Europe. The project is conducted as multi-national initiative from the country delegate group from the EBJIS. Several Country Delegates members have started to estimate the overall number of cases of PJIs for Europe and to derive the associated health-economic costs.