The proposed project involves the implementation and evaluation of an intervention program to promote healthy aging among sedentary middle-aged and older adults. The intervention is based on a solid body of evidence showing that negative views on aging (VoA) and low control beliefs are associated with poorer health and a lower likelihood of engaging in health-promoting behaviors. Therefore, this program is designed to increase positive VoA and strengthen control beliefs, and to support individuals in maintaining a physical activity program. This proposal employs a randomized pretest-posttest control group design and includes 100 community-residing adults ages 50-70. All participants take part in an 8-week program comprised of 4 weekly classroom sessions, and a 4-week goal-directed experiential period. The control group receives writ- ten educational materials specific to physical activity and healthy aging. Specific Aim 1 is to evaluate the pro- gram's effect on three key variables: VoA, control beliefs, and physical activity. This aim will be tested with a 2 (condition) x 4 (time of measurement) multivariate analysis of variance (MANOVA) to evaluate both inter- and intra-individual differences. Specific Aim 2 involves the evaluation of a statisticl model to identify causal mechanisms of the intervention. Multivariate multiple regression will be used to test a multiple mediation model, in which the intervention leads to improved VoA and control beliefs, which, in turn, lead to increased physical activity.