Objective To ascertain the effectiveness of the National Arthritis Foundation (NAF) aquatic and on-land exercise programs on functional fitness and perceived ability to perform activities of daily living (ADL) measures in older adults with arthritis. Design The effects of aquatic and on-land exercise intervention programs were analyzed by repeated-measures analysis of variance by using a planned comparison approach with an independent 3×2 (group by test) design. ω 2 analyses were used to ascertain the relative treatment magnitude of each dependent variable. Setting Testing in an indoor track facility; exercise programs conducted in community settings. Participants A volunteer sample of 30 men and women with arthritis (osteoarthritis, n=22; rheumatoid arthritis, n=8), randomly assigned into either an aquatic exercise (n=10), on-land exercise (n=10), or control group (n=10). Intervention Eight-week on-land and aquatic exercise program. Main outcome measures Functional fitness, ADLs, and hand-held dynamometry measures assessed on a 1-day pretest and posttest session, before and after an 8-week exercise program. Results Aquatic and on-land exercise subjects showed significant improvements on 9 of 12 functional fitness, 3 of 4 ADLs, and 7 of 8 hand-held isometric strength tests after their respective exercise programs. No significant changes were found in any of these measures for the control group. Conclusion Both NAF exercise programs appear to be effective in improving functional physical fitness and perceived ability to perform ADL measures in older adults with arthritis.