The complex system of processes and structures which protect an organism from disease is known as the immune system. The area of study within biology which focuses on the immune systems in organisms is known as immunology. It analyzes the relationship between pathogens, body systems and immunity. Some of the major areas of study within immunology are clinical immunology, ecoimmunology and developmental immunology. The disorders of the immune system are studied within clinical immunology. These disorders are categorized into immunodeficiency and autoimmunity. Ecoimmunology studies the relationship between an organism’s immune system and the biotic and abiotic environment. This book unfolds the innovative aspects of immunology which will be crucial for the progress of this field in the future. While understanding the long-term perspectives of the topics, it makes an effort in highlighting their impact as a modern tool for the growth of the discipline. This book includes contributions of experts and scientists which will provide innovative insights into this field.