 The aim of the study is to assess the impact of different surgical and antibiotic therapies on patients admitted for a septic or aseptic revision of the hip, knee or shoulder prosthesis. The decision whether the implant will be retained or removed or antimicrobial treatment is based on criteria of each participating center specialists.The success of different treatment algorithms will be measured in terms of infection free interval, functional outcome and quality of life. All consecutive patients who need a revision surgery to the hip, knee or shoulder will be included. Furthermore the study will investigate different diagnostic tests microbiological and histological for the diagnosis and the discrimination of septic and aseptic causes in prosthesis failures. Pathogens microorganisms isolated from puncture of the joint, tissue samples sonication fluid and blood will be collected to establish a biobank.The samples are obtained preoperatively and intraoperatively as part of routine care practice. The study is not randomized. 