Office work-related upper extremity symptoms and disorders have been associated with static work posture, repetition, and inadequate recovery in the anatomic structures of the neck and upper extremities. Despite these associations, relatively little research has been conducted on the development of practical measures of these ergonomic exposures. The present study examines the measurement properties of an upper-extremity-specific self-report index of ergonomic exposures. Ninety-two symptomatic office workers completed a Web-based questionnaire measuring demographic variables, ergonomic exposures, pain, job stress, and functional limitations. Comparisons of internal consistency, construct validity, and discriminative and predictive abilities were made between the self-report index and an observational exposure assessment checklist. Results indicated that the self-report index had acceptable measurement properties. Furthermore, higher levels of self-reported ergonomic exposures were associated with upper extremity pain, symptom severity, and functional limitations. In contrast, higher levels of observed exposure were related only to lower levels of general physical function. The self-report measure has potential for use in occupational health surveillance programs for office work environments and as an outcome measure of ergonomic exposure in intervention trials. These results also suggest the need for using multiple methods when assessing ergonomic exposures.