The response rates of unselected patients with lung cancer to PD-1/PD-L1 immunotherapy alone remain low at 20% to 30%, underscoring the ongoing need to optimize immunotherapy for individual patients based on novel molecular markers. Moreover, combining immunotherapy with other forms of treatment such as chemotherapy, radiotherapy, or both may well overcome the development of resistance to immunotherapy and improve the therapeutic ratio. This has been a most exciting time for clinical research on this topic. The concept of combining immunotherapy with stereotactic ablative radiotherapy (I-SABR) has triggered extensive interest, and hundreds of preclinical and clinical studies are now ongoing. I-SABR and other strategies for optimizing immuno-radiotherapy are also being proposed in 2018. There is no doubt that tomorrow's lung cancer patients will be better treated than today's. This book provides unique, up-to-date information about the paradigm shift in biology and technology prompted by the advent of immunotherapy. More is coming. Stay tuned.