Mastocytosis is a rare and multifaceted disease group characterized by mast cell accumulation in the skin and/or internal organs. In its most common form solitary or widespread, often itchy, red-brown skin lesions appear in childhood or during adulthood (cutaneous mastocytosis). The skin lesions are not always easy to recognize by medical professionals; hence, a correct diagnosis is often delayed. In children, the lesions tend to resolve before puberty, whereas most post-adolescent patients experience a chronic course combined with extra-cutaneous mast cell infiltration (systemic mastocytosis). Therefore, adult patients with cutaneous mastocytosis should be examined for signs of systemic involvement. This article describes the symptoms and signs in cutaneous mastocytosis, and provides guidelines based on international consensus documents. In addition, a newly updated classification of different forms of cutaneous mastocytosis is given.