There are only few reports of clavicular duplication in the literature and all authors have agreed that duplicated clavicles are clinically insignificant. This is the first report of this unique association. A 22â€‘yearâ€‘old female student reported with features of neurogenic thoracic outlet syndrome mainly involving C8â€‘T1 components of the brachial plexus, seemingly originating from involvement in costoâ€‘clavicular space. Radiograph of the shoulder revealed clavicular duplication. Neuroâ€‘physiological studies corroborated the diagnosis. Patient responded well to conservative treatment and was in followâ€‘up for 1 year. Radiograph of the shoulder should be included in the workup of neurogenic thoracic outlet syndrome and anomalies of clavicle should be looked into and ruled out along with other common causes. Patient and symptom directed approach with dedicated physiotherapy and occupational therapy is required for optimum outcome.