OBJECTIVE:: A work function measure specific for persons with prodromal Huntington disease (HD) was created to assist with workplace accommodations. METHODS:: A self-report HD Work Function (HDWF) measure was developed from focus group and expert validation. RESULTS:: Pilot studies with 238 people with prodromal HD, and 185 companions; and 89 people without prodromal HD, and 70 companions indicate that HDWF has acceptable internal consistency (Cronbach α = 0.77), acceptable interrater reliability (r = 0.58), and acceptable convergent validity with selected items from the Endicott Work Productivity Scale (r = -0.56), Social Adjustment Scale-Self Report (r = -0.29), and Everyday Cognition (r = -0.70). The HDWF can distinguish between people with prodromal HD and people with an HD family history who do not have prodromal HD (P < 0.0001). CONCLUSIONS:: The HDWF is a brief self-assessment that may be used to monitor work function. Copyright © 2012 by American College of Occupational and Environmental Medicine.