Abstract: Although wisdom is thought to be a strong predictor for many attributes of aging well, the concept of wisdom still lacks a comprehensive, directly testable scale. Quantitative and qualitative interviews with a sample of 180 older adults (age 52-plus) were conducted to develop a three-dimensional wisdom scale (3D-WS) and to test its validity and reliability. Wisdom was operationalized and measured as a latent variable with cognitive, reflective, and affective effect indicators. Respondents completed a self-administered questionnaire, which included 114 items from existing scales and 18 newly developed items to assess the three dimensions of wisdom. The final version of the 3D-WS consists of 14 items for the cognitive, 12 for the reflective, and 13 for the affective component of wisdom. Results indicate that the 3D-WS can be considered a reliable and valid instrument and a promising measure of the latent variable wisdom in large, standardized surveys of older populations.