Since the identification of the cholesterol derivative 1,25-dihydroxy-vitamin D3 and its analogues as potent immunomodulatory, proliferation- and differentiation-regulatory molecules, the amount of data available on the effects of these agents on the skin and its appendages has grown exponentially. This review outlines recent progress in the understanding of the molecular biology and pathophysiology of vitamin D, and new strategies for the treatment of skin diseases are discussed. Focusing on psoriasis and preliminary clinical experiences, we discuss possible therapeutic targets and perspectives for these multifunctional steroid hormones in dermatology.