This article is inspired by the development of professional creative arts therapy (CAT) and the expansion of the application of the CAT services in Estonia. CAT has four specializations: (visual) art therapy, music therapy, dance movement therapy, and drama therapy. CAT is determined as a reasonable, purposeful, and planned psychotherapeutic and supportive use of creative arts based methods and techniques in a clearly defined client-therapist relationship. Creative arts therapists are working in health and social care institutions, rehabilitation centres, and schools. Due to the variety of approaches of CAT, there are different interpretations used by both service providers and users. Consequently, the heterogeneity of the approaches of CAT and common features of CAT are discussed. The general criteria relying on the professional standard of creative arts therapists and the model of intervention levels of CAT, consisting of diagnostic, psychotherapeutic, functional, recreative, and palliative levels, are introduced. The article gives also an overview of the research findings and treatment outcomes of CAT.