This book focuses on the role of the immune system in biomaterial applications. In the field of biomaterials there are significant advances in using immunomodulation techniques to improve the success rates of implantable materials. For better understanding of such techniques it is required to have a full grasp of the biomaterial immune system interactions. This book has dedicated chapters for explaining immune cells taking part in immune response to biomaterials/immune systems interface and to greatly enhance the understanding of why the human body reacts to implants and how to solve this problem. Some common implants are dental implants, hip prosthesis and knee prosthesis, etc.