The Activity Card Sort is a valid and reliable assessment tool that was created to assess Participation. It has been translated to several languages and adapted to different international cultures. The most recent version of this tool is the Arabic Heritage Activity Card Sort (A-ACS). The purpose of this study was to establish the psychometric properties of the new Arabic version in Jordanian adults. Forty three Jordanian patients with multiple sclerosis (MS) and 62 healthy adults were recruited to test the psychometric properties of the tool. The A-ACS correlated moderately with the participation index of the Mayo-Portland Adaptability Inventory (r = −0.458, p < 0.00) (concurrent validity), was able to discriminate between patients and healthy participants on the current and retained levels of participation (F = 5.09, p < 0.03; F = 6.01, p < 0.02, respectively) (discriminative validity), and correlated moderately with the total scores of the Mayo-Portland Adaptability Inventory (r = −0.458, p < 0.00) and the total score on the Arabic version of the self-report Performance Assessment of Self-care Skills (r = 0.581, p < 0.00) (convergent validity). The tool also showed good test–retest reliability (r = 0.80, p < 0.00) and excellent internal consistency (α = 0.90). The Arabic Heritage of the Activity Card Sort is a valid and reliable tool for Arabic-speaking occupational therapists to use when assessing participation in Jordanian patients with MS or healthy adults. Limitations of this study include using only one diagnostic group from Jordan and examining only the Recovery and Community Versions of the tool. Future studies are needed to examine further psychometric properties for patients with different diagnoses and from different countries in the Arabic region for all three versions of the A-ACS. Copyright © 2012 John Wiley & Sons, Ltd.