Of all cancers, > 50% currently occur in individuals >or= 65 years of age and this figure is expected to rise to 70% by 2030, due to a progressive expansion of the older population [1]. Clinical trials are needed in order to establish the benefits and risks of antineoplastic treatment in older individuals. It is reasonable to expect that the costs of these trials may be higher than in younger individuals, as older patients are more vulnerable to therapeutic complications and may need more supportive care, and the benefits of treatment may be less because of a reduced life-expectancy and competitive causes of death [2]. This article explores a cost-effective approach to clinical trials in older individuals, after reviewing the basic concepts of economic analysis and unique aspects of geriatric oncology that may affect the cost of treatment. In the process, the cost differences of cancer treatment in younger and older patients will be explored.