This case study, one in a series of research efforts designed to examine the utilization of the Administration on Aging's research, describes the different types of uses of materials produced by a research project on improvement of transportation services for the elderly. (The materials are a state-of-the-art report, planning handbook, and site-assistance kit.) Illustrative vignettes describe how three user groups--policy makers, planners, and service operators--used the research results. In general, these uses are defined: (1) federal policymakers integrated information from the transportation program into new programs and plans; (2) state and area planners used the planning handbook to facilitate provision of training and technical assistance to local service operators and dissemination of documents and information in response to individual inquiries; and, (3) service operators used the handbook to design and run new "demand-responsive" transportation services in rural and urban communities. Five propositions regarding conditions necessary for research utilization are suggested: extensive social networking, interventions to boost utilization, vigorous information dissemination, synthesis of previous findings into the research, and emphasis on development rather than on research. (YLB)