He trained in Plastic Surgery in a number of London units and passed the Plastic Surgery Fellowship of the Royal College of Surgeons in 1998 FRCS (Plast). His areas of special interest include head and neck and breast reconstruction and all areas of aesthetic surgery. Following the completion of his surgical training in England he was awarded a travelling fellowship by the British Association of Plastic Surgeons and spent a year in Paris. During his time abroad he gained considerable experience in both reconstructive and aesthetic surgery.
Mr Withey was entered into the Specialist Register for Plastic Surgery in 2001. He is a full member of the British Association of Plastic Surgeons (BAPS) and the British Association of Aesthetic Plastic Surgeons (BAAPS). He has been actively involved in Plastic Surgical research and has presented national and international surgical meetings. He has published more than thirty peer-reviewed papers in Plastic Surgery and maintains an active interest in surgical research, havingrecently been awarded a research grant by the Royal College of Surgeons.

Mr Withey is on the academic committee of the European Course for Head and Neck Reconstruction, and teaches on the Paris course twice a year. He is a tutor on the European Microsurgical course in Milan and regularly teaches Plastic Surgery trainees at the Royal College of Surgeons. He is a Consultant Plastic Surgeon at the Royal Free Hospital, London. His interests include all aspects of aesthetic surgery, specifically facial and breast surgery.