The objective of this study was to develop the Pro-Change Functional Well-Being Scale, a measure that provides an informative evaluation of general functioning loss due to well-being-related barriers. Exploratory and confirmatory analyses on data from 642 individuals supported a one-factor solution with good model fit. A strong positive correlation existed between the Pro-Change Functional Well-Being Scale and Well-Being Assessment for Productivity. Initial construct validity was demonstrated by predictable relationships between functioning loss and other measures of health and well-being. This initial psychometric evidence suggests that the Pro-Change Functional Well-Being Scale is a reliable and valid assessment of functioning loss due to common well-being-related barriers.