ERP therapy (exposure and response prevention) and ExRP (exposure and ritual prevention) are psychotherapies used to treat obsessive-compulsive disorder (OCD). ERP was developed in the 1970s and 1980s by psychologist Edna Foa and colleagues at the University of Pennsylvania, although the basic principles of the treatment were well known for decades prior.

Subsequent innovations in this therapy resulted in its being given a new name: Exposure and Ritual Prevention (ExRP). This created some confusion as the one therapy was now known by two names. For all practical purposes, there is no difference between ERP and ExRP. This piece will provide information about what ERP / ExRP therapy involves, and how they it can helpful to people suffering from OCD.