This study was a left-right comparison of the efficacy of 0.005% calcipotriol ointment and 5% coal tar ointment in conjunction with sun exposure in 10 patients With stable plaque psoriasis. After four weeks of therapy, the calcipotriol treated site showed a significantly faster fall in PASI compared to the coal tar treated site. At eight weeks, this difference was not significant with both sides showing comparable improvement in lesions, as shown by PASI values. There were no significant side effects froth either therapy. We conclude that both calcipotriol and coal tar ointments have comparable efficacy in treating stable plaque psoriasis when used simultaneously with still exposure, although the initial response to calcipotriol is faster.