Integration of shunt capacitor banks and distributed generators in distribution system plays major role in the planning of electric power distribution systems. While planning an engineer must look after the technical as well as economic benefits of compensation. Optimization is one good approach to achieve the best possible benefits from the integration of CBs and DGs in short time. This book presents simultaneous optimal allocation of shunt capacitor banks and distributed generators in radial distribution systems using nature and bio inspired optimization algorithms. It includes mathematical modelling, implementation of various optimization approaches, various distribution systems and comparative analysis. I hope this book is most useful source for researchers and masters level students who are perusing research in electrical power distribution systems.