  We summarize progress in the development and application of metamaterial
structures utilizing superconducting elements. After a brief review of the
salient features of superconductivity, the advantages of superconducting
metamaterials over their normal metal counterparts are discussed. We then
present the unique electromagnetic properties of superconductors and discuss
their use in both proposed and demonstrated metamaterial structures. Finally we
discuss novel applications enabled by superconducting metamaterials, and then
mention a few possible directions for future research.
