Mr Benjamin trained in Brighton, The Western Eye Hospital, Moorfields and The Oxford Eye Hospital. He was appointed as a Consultant in 1990 and since then has developed interests in Cataract surgery, the management of Diabetic Retinopathy including the use of early vitrectomy and surgical training. He was the first chairman of the Surgical Skills Sub-committee at the Royal College of Ophthalmologists during which he helped to develop the College microsurgical skills courses and chaired the committee, which updated the latest College cataract surgical guidelines. He has served as the Chairman of the Education Committee and Senior Vice President of the College.

He has also served as the programme secretary to the ophthalmic section of the Royal Society of Medicine and is the Immediate Past-President for this section (October 2020-2022). He was until recently the chair of the microsurgical skills committee at the RCOphth. He has served on the council of UKISCRS and is a past- President. He has been a volunteer faculty member for Orbis the flying eye hospital charity and is chairman of its programme committee for Europe Middle East and Africa. He was recently co-awarded the inaugural Jack Kanski prize for an outstanding educator by the RCOphth, and also an Honorary Fellowship of the Royal College of Ophthalmologists.