UVA (320-340nm) light is an effective yet innocuous therapeutic modality for the treatment of patients with systemic lupus erythematosus (SLE). The long term objectives are to learn whether UV-A1 light can control disease long term, whether it becomes toxic with prolonged use, and how its delivery can be optimized for both short and long term trials. The specific aims will be to evaluate over the short and long term dose level, required frequency of treatments, the effect of ambient temperature during treatment, the most advantageous lamp placement, the interaction of UV-A light with other therapies and the mechanisms of UVA's action. The observations will serve to develop this therapy, the first of its kind.