High-Gradient Breakdown in Normal-Conducting RF Cavities

Over the last few years it has become apparent that RF breakdown and the damage that it can cause are critical issues for normal-conducting high-energy linear colliders. Substantial efforts to address RF breakdown issues have been launched within the linear-collider community. The ideas about the physics of breakdown, experimental results, methods to increase achievable gradients and methods to avoid damage that have emerged from the studies are reviewed.