In day-to-day activities, portable wireless and mobile communication devices and technologies are becoming an integral part of human life. These systems need compact, high gain, high directivity and large bandwidth antennas to communicate voice, video, data, and multimedia information at high data rates. The limitations of microstrip patch antennas restrict to fulfill these challenges. This book presents different configurations of planar metamaterial antennas to overcome these limitations. In this book, metamaterial loaded ESAs, MI waveguide loaded microstrip patch antennas have been presented to considerably reduce the size and to enhance the gain, bandwidth and directivity of microstrip patch antennas. One of the salient features of this book is metamaterial loaded wearable microstrip patch antennas. These antennas have been designed, simulated, manufactured and tested. Photographs of fabricated antennas and experimental set-up with simulated and measured results have been reported in this book. The concept of metamaterial antenna array is also presented. This book is useful for microwave and antenna researchers, academicians, students, and practicing engineers/technicians.