Another aspect that could enhance the dissemination of evidence-based treatments as well as considerably reduce the costs is the use of the Internet. A number of sistematic reviews has shown that Internet-based treatments yield similar results when compared to face-to-face therapy. Nevertheless, most of these programs are focused on a single disorder since a few Transdiagostic Internet-based treatments have been developed and tested by means of randomized controlled trials so far. Furthermore, no studies on efficacy of Internet-based Transdiagnostic vs Treatment as usual (TAU) have been carried out in specialized care. Therefore, we have developed a Transdiagnostic Internet-based protocol treatment (Emotion Regulation Protocol) based on the Unified Protocol proposed by Barlow, that also includes components of emotion regulation and acceptance.