Mobility represents a critical component in the functional and disability assessment of older adults because it is related significantly to the maintenance of elder autonomy and independence. The authors' primary purposes are to raise the consciousness of geriatric social workers about the need to consider mobility as an important aspect of older persons' lives in the context of their environment, and to describe the application of a new strategy of mobility assessment that complements existing methods. First, an overview of the literature is provided that emphasizes the clinical relevance of mobility within the context of functional and disability assessment. Second, an application of the Life-Space Mobility Assessment (LSMA) with seniors is described as complementing the more traditional but less precise and sensitive methods of functional assessments typically used by social workers and other health care practitioners. Theoretical links to person-in-environment and ecology models are reviewed, and the implications for training, practice and research for social workers are discussed. © 2001 by The Haworth Press, Inc. All rights reserved.