This book presents a new global optimization technique named biogeography based optimization (BBO) for antenna design. BBO is a novel evolutionary algorithm and is still in its infancy. It is employed for the first time for solving electromagnetic optimization problems. BBO is a new inclusive vigour based on the science of biogeography. Biogeography is the schoolwork of geographical allotment of biological organisms. The BBO method is a general stochastic optimization technique for solving both continuous and discrete multi-objective optimization problems. BBO employs migration operator to share information between the problem solutions. The problem solutions are identified as habitat and sharing of features is called migration. The proposed optimization method is used in various linear antenna arrays, rectangular antenna arrays, circular antenna arrays, ring antenna arrays and Yagi-Uda antenna arrays. The results obtained demonstrate the validity and efficiency of the proposed BBO method.