Participants will meet with a Certified Fitness Trainer and engage in shared goal setting and selection of a CDC-recommended exercise program for OA that best fits their needs and preferences, specifically addressing any identified barriers. The Trainer will use programs from a vetted list of programs that are appropriate for older adults with knee OA, and modify as needed. This list will be developed with the Certified Fitness Trainer and the PI. The Trainer will be available to answer questions and will contact each participant by phone every two weeks to find out how participants are doing; make adjustments to the program, if needed; and provide motivation and encouragement. Feasibility will be evaluated by quantifying the proportion of participants who complete the assessments within a 3-month period. Potential effectiveness will be evaluated based on pre-post difference in the mean number of self-reported minutes spent in mild, moderate, or vigorous exercise in the previous week; the proportion of participants who have adopted any exercise routine, and change in health goal attainment confidence. Pain as measured on a 10 cm visual analog scale will be collected as an exploratory measure. (see descriptions of measures below).