Research suggests that differences in levels of physical activity in older populations may be due to a variety of factors such as personal and social variables, levels of health and functional capacity, and characteristics of the built environment. In this study, the Healthy Aging Research Network centers will collaborate with senior-serving organizations in diverse communities to identify participants over 65 years old. The participants’ levels of walking will be studied in relation to the built environment and each subject’s level of functional capacity. The investigators will also examine how the participants’ perceptions of their environment influence levels of walking. Enhancing our understanding of environmental correlates of physical activity among older adults will inform the policy discussion as to the best environmental changes for promotion of physical activity for older adults.