The number of older individuals with cancer is increasing exponentially, mandating that oncologists contemplate more comprehensive and multidisciplinary approaches to treatment of this cohort. Recruitment of assessment instruments validated in older patients can be invaluable for guiding treatment and decision-making by both patients and providers, and can arguably contribute to improving outcomes and health-related quality of life. The Comprehensive Geriatric Assessment is one such validated instrument that can be used by oncologists to assess patient readiness and appropriateness for prescribed cancer therapy. As a multidisciplinary diagnostic and treatment process, it comprises functional status, cognitive status, social support, and advance care preferences, and is an ideal instrument for evaluating complex older individuals. It is well established that many older individuals with cancer travel with multiple comorbid illnesses, including cognitive impairment, and when presented with a cancer diagnosis struggle to choose from multiple treatment options. In addition to the complete medical history, the ability of patients to decide on a course of therapy in concert with their oncologist is critically important. Alternatively, many oncologists are conflicted as to whether true informed consent for treatment can be obtained from many older patients. Having a roadmap to decision-making capacity is therefore an inescapable imperative in geriatric oncology, because careful attention must be directed at identifying older patients with cancer who might benefit from these assessments and the individualized treatment plans that emerge.