Cancer nanotechnology and cancer immunotherapy are two parallel themes that have emerged over the last few decades in the search for a cure for cancer. Exciting applications can emerge at the intersection of these two fields. However, it is important to learn from the past successes and failures of cancer nanomedicines for its future applications in cancer immunotherapy. This review discusses the two key parameters that defined clinical success in the case of cancer nanomedicines: (i) physicochemical design principles, and (ii) clinical trial design, which are frequently overlooked in most analyses of the state of the field. Learning from the design principles that defined success for the clinically-used cancer nanomedicines can enable the design of next-generation nanomedicines that can address some of the emerging challenges in cancer immunotherapy, for example (i) enabling combinations of molecularly targeted therapies with immunotherapies that are pharmacologically incompatible; (ii) early monitoring of efficacy of immunotherapies; and (iii) personalizing an immune response to a patient's tumor. Currently, only a subset of patients treated with immunotherapy exhibit durable response; the integration of nanomedicine and immunotherapy to address the above challenges can lead to new paradigms in the treatment of cancer.