Sir, Netherton syndrome (NS) is a rare autosomal recessive disorder of keratinization. It is caused by a mutation of the SPINK5 gene that encodes a multidomain serine protease inhibitor (LEKTI) predominantly expressed in epithelial and lymphoid tissues (1). Clinical presentation is characterized by the triad of (i) ichthyosis, i.e. ichthyosis linearis circumflexa (ILC) and/or congenital ichthyosiform erythroderma (CIE), (ii) hair shaft abnormalities, i.e. trichorrhexis invaginata, pili torti and/or trichorrhexis nodosa, and (iii) atopic manifestations, mainly atopic dermatitis, eczema-like rashes and hay fever. The clinical course is chronic, with recurrent exacerbations of atopic and ichthyosiform lesions. Several treatment approaches, including topical as well as systemic corticosteroids, antibiotics and retinoids, have been investigated with varying, often disappointing, results. UVB phototherapy and topical psoralen plus UVA (PUVA) photochemotherapy are effective, but treatment is accompanied by acute adverse effects and long-term toxicity. As UVA1 (340 – 400 nm) phototherapy has been found to be an effective and well-tolerated treatment for psoriasis in immunosuppressed patients (2) and atopic dermatitis (3), we investigated its use in the treatment of NS.