SUMMARYSkin may be affected by non-Hodgkin lymphomas, and it is the second most frequently involved extranodal organ, after the gastrointestinal tract. Cutaneous lymphomas may originate from T, B, or NK lymphocytes. Diagnosis is difficult, and knowledge of these diseases is important to ensure their detection and adequate treatment and follow-up. Clinical picture is heterogeneous, and histology is essential to confirm the diagnosis. The classification is given by the correlation between clinical findings, histology and immunophenotyping. Therapeutic options include skin-directed therapies, immunomodulatory or low-dose immunosuppressive drugs. Rare cases of aggressive disease require systemic multidrug chemotherapy. The purpose of this review is to describe the ontogeny of T, B and NK lymphocytes, and to detail the most accepted classification of cutaneous lymphomas, proposed by the World Health Organisation and European Organisation for Research and Treatment of Cancer. Treatment of cutaneous lymphomas will be briefly discussed.