A new classification of inherited ichthyoses is presented based on clinical features, genetic background and pathophysiology. Ichthyoses are disorders of cornification and may be part of syndromes. Ichthyosis vulgaris, X-linked ichthyosis, autosomal recessive congenital ichthyosis and syndrome-related variants are described. Severe forms can be potentially life-threatening. Dry scaly skin can be disabling and time-consuming, as the patient needs topical therapy and sometimes also systemic retinoids. Treatment today is symptomatic, but hopefully new knowledge will lead to targeted therapies.