Review of high intensity ion source development and operation.

The Electron Cyclotron Resonance Ion Source (ECRIS) has transformed the nuclear physics research field over the last 47 years. Today, the performance of ion sources is the first parameter that defines the design performance of existing facilities as well as the design approach and performance of new facilities. In this paper, I will review the current "state of the art" performance capabilities for ECRISs as well as other ion sources and how those current capabilities form the primary design criteria for new nuclear physics facilities and set the limiting performance for existing facilities. I will close with a short-term look into the future for these ion sources and other competing types.