This book presents the basic of multipliers and its practical implementation microwave frequencies employing simpler techniques. This book provides a simple realizable multiplier approach with diode, transistor and mixer based topologies. The topologies covered in this book are planar, easier implementable and comprehensively brings out the practical challenges in the realization. Step recovery diode and FET based multipliers at microwave frequencies are designed using standard software simulation keeping fabrication limitations into consideration. The simple non-linear modelling approach is also presented and incorporated resulting in the close match between predicted and measured results. The presented approach is scalable and implementable. The other aspects such as RF and transmission lines fundamentals, diode basics and system level simulation covering various planar circuits are also covered which will provide better understanding. The book brings out concept to development approach along with glimpses of future topologies for providing better insight to students and researchers.