To identify the range of activities limited following adult traumatic brachial plexus injury and triangulate these with existing patient-reported outcome measures identified from the literature.A qualitative cross-sectional design.Adults with traumatic brachial plexus injury and expert clinicians.Using an International Classification of Functioning, Disability and Health (ICF) framework, participants identified day-to-day activities that are limited following traumatic brachial plexus injury. Two independent reviewers classified all reported activities into the Comprehensive ICF Core Set of Hand Conditions (CCS-HC) activity domains. Reported activities were triangulated with patient-reported outcome measures identified from the brachial plexus injury literature.Fifty-one participants (21 adults with brachial plexus injury, 30 expert clinicians) generated a total of 522 items. The inter-rater reliability for classification to CCS-HC domains was excellent (k = 0.94, 95% confidence interval (95% CI) 0.92-0.96). Activities reported by patients and clinicians represented all 29 CCS-CH activity domains. Five activities (2%) could not be classified to any ICF domain. Fifteen CCS-HC activity domains were represented in the Disabilities of Arm, Shoulder and Hand (DASH) and ABILHAND, 2 measures currently used in the brachial plexus injury literature.Adults with a brachial plexus injury report a range of activities that are limited following injury, and are under-represented in currently used patient-reported outcome measures. The activities reported in this study could be used to inform the development of a new brachial plexus injury targeted questionnaire.