The ability to apply large-scale screening formats to measures of ion channel function offers immense opportunities for drug discovery and academic research. Technologies have been developed over the last several years that now provide the ability to screen large numbers of compounds and natural products on ion channel function to find novel drugs. Application of these technologies has vastly improved the capabilities of ion channel drug discovery and provides an avenue to accelerate discoveries of ion channel biology. These advances have largely arisen from the development and application of instruments and reporters of membrane potential and ion movements in cells used to measure functional activity of ion channels. This article endeavors to describe the practical applications of these technologies in developing, validating, and implementing high throughput screening assay formats to different types of ion channels.