This paper presents the development of an Immersive Virtual Technology (IVT) system serving a community of practice consisting of psychotherapists who use virtual environments for therapy and treatment of anxiety disorders. The psychosocial theoretical background includes the ethnomethodological approach, Situated Action Theory and the Intersubjectivity of the Utterance model. The dialogical importance promoted at each level of the analysis phases becomes the key to a deeper and more fluid understanding of the assumptions and meaning that guide the actions of and interactions between therapists and patients. The entire system design process is inspired by a dialogical perspective, which aims to effectively and non-rigidly integrate the design stages, analysis in context of use, ergonomic evaluation, creation of the virtual reality (VR) system, and final work on the clinical protocol in use.