Twenty-five patients suffering from severe polymorphic light eruption (PLE) were randomized to either photochemotherapy (PUVA) or narrow-band phototherapy (TL-01 UVB) treatment in early spring; patients receiving UVB were given placebo tablets to achieve a matching therapy procedure. During the 4 months following treatment, patient exposure to solar UVB was monitored with polysulphone badges. PLE occurrence, severity, and restriction of outdoor activity were recorded, using weekly diary-sheets. Analysis of covariance on this data, using the logarithm of UVB exposure as the explanatory variable, showed no significant differences between the treatments. TL-01 UVB is an effective alternative to PUVA in the management of PLE.