Corticosteroid therapy for pulmonary sarcoidosis is not standardized. There is no consensus on which patients should receive treatment, how patients should be monitored, and the dose of corticosteroids once the decision to treat has been made. These issues are important for several reasons. First, inappropriate use of corticosteroids may result in unnecessary toxic reactions. Second, inadequate use of corticosteroids might result in permanent pulmonary and extrapulmonary organ dysfunction from sarcoidosis. Third, patients who are inappropriately labeled as "corticosteroid failures" may be subjected to other potentially toxic drugs or even lung transplantation. Corticosteroid dosing involves six phases: (1) initial high doses to control inflammation; (2) tapering to a maintenance dose that will continue to suppress the inflammation but lessen the risk of corticosteroid toxic reactions; (3) continuing to receive the maintenance dose until a decision to taper off corticosteroids is made; (4) tapering off corticosteroid therapy; (5) observation for relapse; and (6) treatment if relapse occurs. Although these phases of treatment have been alluded to in the literature, few of them have been studied rigorously. This article describes the use of corticosteroids for pulmonary sarcoidosis in terms of the above six phases. The proposed dosing schedules are based on the natural history of the disease and the results from published treatment studies.