Aggressive fibromatosis (AF) is a locally aggressive infiltrative low-grade benign tumor that accounts for approximately less than 3% of all soft tissue tumors. In the head and neck region this tumor tends to be more aggressive and associated with significant morbidity. Aggressive surgery is a viable management option and may be successfully used as a single modality treatment, or in combination with radiotherapy. We report a rare case of AF in a 38 year old female, who presented with a painless mass over the left supraclavicular fossa, extending inferiorly into the thoracic inlet, which was excised successfully in toto with the help of cardiothoracic vascular surgeon (CTVS)