With the intention of informing the broad community of fusion researchers, the background, status, and potential future uses of superconducting magnets are covered. After a brief explanation of the principles of superconducting magnets, the technological basis is examined. Major emphasis is on the description of activities in the worldwide development and application of superconducting magnets in fusion programmes through mid-1981. Evaluation of progress and projection of needs for fusion reactors lead to the conclusion that superconducting magnets can be available when required.