The objective of this research was to develop indicator scales for major health and social problems of individuals aged 65 or over who live in the community. A semistructured interview technique, the Comprehensive Assessment and Referral Evaluation (CARE), was used in two large surveys in London and New York City. Twenty-two indicator scales were developed by using items that met certain clinical and statistical criteria. These indicator scales are intended for use in developing a general taxonomy of the problems of older individuals, for clinical assessment and referral of such individuals, and for use in geriatric epidemiological research. The scales were developed to be comprehensive with regard to the CARE, to be relatively independent of one another, and to have satisfactory content, clinical, and face validities, and interrater and internal consistency reliabilities.