The use of heat, in one form or another, and the application of infectious materials in and around cancerous tissues, in one form or another, as cancer cures, can be traced back to ancient times. While there is no recorded documentation of the reason for our ancestors incorporating these two modalities in the therapeutic armamentarium against cancer, it will not be a wild speculation that they might have intuited that besides having direct anticancer properties, both could “boost” the fighting power (i.e., “immune responses”) of cancer patients. Of interest, the use of infectious agents (germ therapy) against cancer remained in practice throughout the ages, and modern medical science agreed that both do indeed have immunogenic properties! Over time, the medical science vastly expanded our knowledge on how the immune system operates or fails to operate against cancer and added new agents and methods – e.g., certain bacteria or bacterial products, immune system-based cytokines, lymphokines, cells such as lymphokine-activated killer (LAK) cells, in vitro expanded tumor infiltrating lymphocytes (TILs), dendritic antigen presenting cell-based “vaccines,” synthetic peptide antigens, etc. The overall outcome of “tumor Immunotherapies” has, however, been mostly disappointing although certain types of bladder cancers have shown gratifying results with intracavitary instillation of the bacterium BCG (Bacillus Calmette-Guerin) and TIL therapy proved to be quite successful in some subsets of cancers. Unfortunately, these small gains could not, however, overcome the cumulative disappointments from wave after wave of raised expectations followed by dashed hopes and consequent skepticism over the very credibility of the discipline of “Tumor Immunology” itself. Fortunately, the recent development of two bona fide immune-based strategies – immune checkpoint inhibition (ICI) blockade by antibodies and chimeric antigen receptor (CAR) T cell-based adoptive therapy – have, finally, ushered in the long-waited positive results in the field of “Tumor Immunotherapy” for the Nobel committee to recognize the two principal scientists – who developed the successful ICI blockade-based strategy first – with the prize in 2018!