The field of Fresnel zone plate antennas has seen extensive research and development in the last several years. Scores of articles and three books have been published recently. Zone plate antennas are being used in applications such as communications, radar, radiometry, and guidance, where they offer lower weight and volume, as well as simplicity of design. This course provides attendees with the basic principles of phase-correcting Fresnel zone plate antennas at millimeter-wave and terahertz frequencies. The course concentrates on describing characteristics such as antenna gain, bandwidth, frequency dependence, far-field patterns, efficiency, aberrations, off-axis performance, focal behavior, and feed considerations for zone plate designs having focal lengths and diameters that are similar in size. Their performance is comparable or sometimes superior to a standard lens. Many practical and useful examples are included. Attendees will become fluent with how one designs zone plate antennas for varying applications. The effects of going to the higher frequencies will be described.