Indoor walking is a convenient and safe means to exercise, especially for long-term care residents who may spend the majority of their time indoors.  In particular, due to mobility deficits, frail senior residents can be highly sensitive to and rely heavily on the environment to provide support for exercise.  This dissertation study explored the relationship between physical features of corridors in assisted living facilities and residents' walking behaviors in central Texas.  Residents' perceptions of corridor walkability were also assessed to see how it influences this relationship.  Focus groups of residents, surveys of residents and administrators, and photographs of environments with varying degrees of physical features were used to collect information on how residents use and view corridors for walking.  The study aimed to provide a tool for accessing corridor walkability and recommendations for designing walkable facilities for the frail elderly.