In this book we attempt to apply swarm intelligence with numerical optimization techniques to solve multiobjective engineering problems. So, a hybrid algorithm that combines both of the trust region algorithm (numerical optimization technique) and particle swarm optimization (swarm intelligence method) to solve multiobjective optimization problems is presented. In addition, the new algorithm implemented to solve multiobjective engineering component design problems and the environmental economic dispatch problem to demonstrate the superiority of our approach and confirms its potential to solve engineering applications.