Remote ischemic preconditioning, produced by a brief ischemic insult to one area of the body to induce protection at a remote site, was first described more than 30 years ago. Since then, nearly 2,000 publications have examined underlying mechanisms and clinical effects in both preclinical studies and clinical trials. Although the procedure is well tolerated and effects have been demonstrated across multiple organs, controversy remains as to its efficacy and mechanism of action. Although large pragmatic trials in cardiac surgery have failed to show protection from acute kidney injury, new evidence has rekindled interest in this potential therapy.