In this book, dielectric-based techniques for antenna array are reviewed. It includes classifications of dielectric antenna designs, and studies on their operations. Wideband, high-gain, high efficiency dielectric antennas and arrays are constructed as examples for microwave and millimeter-wave communication applications. Technologies are described that overcome the basic limitations on the antenna and array. The authors also discuss the fabrication of the dielectric antenna array and its tolerances. These discussions constitute the superior and inferior of the dielectric antenna, and its potential to be a cost-effective candidate for the wireless communication applications.