Only the modification of natural steroids in the middle of the last century gave insights into the structural requirements for the biological activity of the glucocorticoids (GC). While the delta-4,3-keto-11-beta, 17-alpha,21-trihydroxyl configuration is needed for the GC-activity, an artificial additional double binding in position 1 and 2 lead to a four fold increase of the GC-activity. Of the artificial GC, prednisolone is the most frequently used compound and essential in the therapy of vasculitis today. Dosage, duration and way of application depend on the diagnosis, disease stage, -extend as well as -activity. Considering the use and side-effects of the GC, experiences from cohort-studies of the late 80-ties help at clinical decision making. For giant cell arteritis (GCA) it was shown, that doses of less then 60 mg/day are needed for the induction of remission. Concerning the visual loss in GCA, time of initiating GC-therapy seems more important than the dosage. In the treatment of ANCA-associated vasculitis therapy with GC, later in combination with cyclophosphamide, lead to a significant reduction of mortality. Due to the fact of an increasing survival rate, therapy-related morbidity becomes a more and more important issue. There is a proven correlation between the dosage respectively duration of the GC-therapy and the risk of GC-associated side-effects, especially the incidence of severe infections. This article gives a short review of the present data of the role of GC in the treatment of vasculitis.