Introduction: Walking is the most common physical activity reported by Canadian adults. Community-ambulation requires many skills such as muscle strength, balance, endurance along with other factors. Clinicians use capacity tests to measure physical abilities to better understand the relationship between what people can do (capacity) and what people really do in their daily lives (performance). Our objective was to determine individual and collective relationships between mobility capacity and walking performance to better understand how to use and interpret tests of capacity in clinical situations. Methods: This study was a secondary data analysis. Baseline data from 168 participants (≥63 years of age) of the GO-OUT study, conducted in 4 Canadian cities (Edmonton, Winnipeg, Toronto, and Montreal), were analyzed. The multiple linear regression analyses included mobility capacity tests (6-minute Walk Test (6MWT), comfortable 10-metre Walk Test (10mWT), 30-second Sit-to-Stand (30sSTS) and Mini-BESTest); and walking performance measures collected with 7-day accelerometry (peak 30-minute cadence, time walked in bouts and steps/day). Frailty status data were used to test for a moderation effect. Results: Outcomes from multiple linear regression models with single capacity measures demonstrated that tests of capacity were positively related with walking performance measures, however they explained only a small amount of the variance in peak 30-minute cadence (24-28%), time walked in bouts (12-17%), and steps/day (18-22%). Analyses of the combined capacity measures using multiple linear regression demonstrated larger amounts of variance were explained in all walking performance measures (peak 30-minute cadence R2 =37%, with 6MWT and 30sSTS significant; time walked in bouts R2 =19%, with 10mWT significant; steps/day R2=25%, with 30sSTS significant; all p ≤ 0.05). Frailty did not moderate any relationships. Conclusion: The 6MWT and 30sSTS are significantly associated with peak 30-minute cadence, which is said to represent the best natural effort in daily life. These two tests assess different aspects of physical capacity and physiotherapists may use them to better understand walking performance of their clients to plan and evaluate treatment progress.