In the last three decades, disability and dependence in old age have become major political and social issues. The World Health Organization and the scientific community have made strenuous efforts to reach a global consensus and to unify concepts and classifications; statistical institutions focus on the creation of sources to enable the study of disability, and society is looking for a healthier aging process, better environment, and appropriate health policies. Spain has followed the pace of this global movement. The National Statistics Institute has conducted three major surveys on disability and dependency (1986, 1999 and 2008). Analysis of their objectives, methodologies, frameworks and applications on the one hand, and data related to older people on the other, confirm the quantitative burden of disability and dependence and also reveals a change in the social and political significance of both old age and disability. Therefore, there is a gradual shift in statistical and policy interests from the causes of disability to their consequences-mainly dependence-and the set of personal and environmental factors that interact with this state.