Background and Purpose: The purpose of this pilot study was to test the reliability and validity of the MotionWatch 8 with older adults. Methods: Participants wore the MotionWatch 8 for 3 days, completed a diary of activities and the Borg Rating of Perceived Exertion (RPE) scale. Results: Evidence of reliability and validity was supported because there was no difference in daily level of activity and that recorded physical activity matched the activity counts. There was a significant difference in Borg RPE scale scores between the sedentary group (Borg RPE scale = 8.6, SD = 3.0) and those with some level of activity (Borg RPE scale = 9.9, SD = 2.3; F = 5.72, p = .02). Conclusion: The findings provide preliminary support for the reliability and validity of the MotionWatch 8 when used with older adults.