Sjögren-Larsson syndrome (SLS) is a recessively inherited disease with congenital ichthyosis, spastic diplegia or tetraplegia and mental retardation, caused by a deficiency of fatty aldehyde dehydrogenase. The aim of this study was to examine all 34 Swedish patients with SLS, emphasizing skin symptoms, dermatological treatment, and neurological symptoms (evaluated in some cases for more than 25 years by one and the same investigator). Structured interviews were conducted with the patients and their close relatives. All patients had generalized ichthyosis. The degree of scaling varied markedly inter-individually from moderate to severe, but there was no obvious change with age. Most patients had pruritus, suffered from hypohidrosis, and had palmo-plantar keratoderma. Nineteen patients (56%) were on oral acitretin and all patients were using some type of topical therapy. Motor disability with spasticity and muscular paresis was most pronounced in the legs and fairly slight in the arms. Twenty patients (59%) were dependent on a wheelchair for mobility. Poor blood circulation in the lower legs and oedematous feet were frequently found in adults. All patients had learning disability, which varied from slight to pronounced and was expressed in their speech disorders. Thirteen patients (38%) were being treated medically for epilepsy and all had photophobia. In conclusion, SLS is a chronic, severely disabling neurocutaneous disease in which optimal dermatological therapy is essential to relieve at least the patient's ichthyosis problem.