Population aging is conventionally understood to refer to increases in the percentage of the population aged 65 and over. Developed economies have for some time shown evidence of this and it is projected that they will continue to experience aging over at least the next 20 years. As the population ages, so the level and pattern of demand for health care is likely to change, and difficulties in financing care to increase. Older persons, for example, tend to consume more health care than those in younger age cohorts, as well as different types of care (for example more long-term care). By the same token, older persons (who are often retired) tend to have less income than those in younger age cohorts. A consequence of this is that they are less able to meet the costs of health care directly (i.e. out of pocket) or contribute through direct taxation to meeting the costs of publicly funded health care. These two factors – growing demand and diminishing income among those for whom demand is expanding – will present challenges to the future finance and delivery of care.