It has been stated in this article and elsewhere that cancer patients aged 65 years and older deserve special attention as a target group for research efforts across the cancer-control spectrum. The available data show that the vulnerability of older persons to cancer is unmistakable. Clinicians will be treating more older patients as the nation ages. The future needs of this segment of the population must be anticipated. In this context, the following generic treatment questions are pertinent. What are the peculiarities of the aged host of which clinicians must be aware in evaluating the older cancer patient? Do various forms of cancer present differently in the elderly? How can be complications caused by the multiple pathologies inherent in the older patient be anticipated? What are the potential hazards and limitations of surgery, radiotherapy, and chemotherapy for older persons with cancer? What is known regarding increased risk of adverse reactions to medications, drugs, and interaction of drugs in older patients? The surveillance data and population estimates and projections presented in this article illustrate the extent of the problems of cancer in the elderly at the macro level. For the individual patient, the special knowledge of aging individuals and their health status based on geriatric medicine and gerontology that has been accumulating for the past several decades needs to be incorporated into the oncology armamentarium that has developed during the same period. The information and expertise from both fields must converge, and new knowledge must be developed at the aging/cancer interface and applied for the optimal treatment of cancer in the elderly.