PURPOSE OF REVIEW: Deep infection following knee arthroplasty is unquestionably a major complication, with potentially devastating consequences. There is a risk of considerable morbidity, the cost of treatment can be high, and the loss of some function is possible even if the infection is successfully controlled. The large number of recent publications devoted to this problem is a testament to its clinical significance. RECENT FINDINGS: The two-stage approach utilizing antibiotic impregnated polymethyl methacrylate spacers has significant advantages when considering exchange arthroplasty. Articulating antibiotic polymethyl methacrylate spacers have become a popular method for staged management of infected total knee replacement. Not only do these spacers significantly improve patient mobility and comfort between stages, but their use also potentially facilitates subsequent reimplantation. SUMMARY: Successful management involves selection of treatment alternatives based on specific criteria. The responsible pathogen, the patients' immunologic status, the chronicity of infection, and the stability of the implant must all be carefully considered. When all of these criteria are favorable, retention of the prosthetic components may be considered, but when any of these criteria are unfavorable retention of the components is more likely to result in treatment failure. For deep infection of more than 3 weeks' duration most expert surgeons recommend a staged approach to management.