ANCA-associated vasculitis (AAV) is a heterogeneous autoimmune disease marked by varying organ involvement and outcomes. Plasma exchange, a method of removing native plasma and replacing it with crystalloid, albumin or donor plasma, can deplete autoantibodies and may help control autoimmune diseases rapidly. In AAV, several randomized controlled trials have been performed but, individually, had mixed results. The best data available, through meta-analysis, suggest the effects of plasma exchange in AAV are limited to improving kidney outcomes with a low likelihood of other benefits but also an increase in the risk of serious infections. As such, the use of plasma exchange in AAV should be limited to patients at risk of a poor kidney outcome as all others are more likely to experience harm than benefit. By estimating the risk of kidney failure and serious infections with and without plasma exchange, healthcare providers can help patients with AAV make informed choices about the use of plasma exchange.