The purpose of this study was to develop measures of perceived social support specific to health-related eating and exercise behaviors. In Study I, specific supportive and nonsupportive behaviors were identified through interviews with 40 individuals making health-behavior changes. In Study II, items derived from the interviews were administered to 171 subjects. Support from family and friends was assessed separately for both diet and exercise habits. Meaningful factors were identified for each of the four scales, and some factors were similar for family and friend scales. Both test-retest and internal consistency reliabilities were acceptable, and six factors can be used as subscales. Social support scales were correlated with respective self-reported dietary and exercise habits, providing evidence of concurrent criterion-related validity. A measure of general social support was not related to the specific social support scales or to reported health habits. These scales are among the first measures of social support behaviors specific to dietary- and exercise-habit change.