Jacek Jerzy Kanski (always known as Jack) was born on 5 August 1939, in Warsaw, Poland. He was the only child of Jerzy Jordan Gustav Kanski and Adela Jozefa née Wroblewska. His father was head of the defence forces of Marshal Edward Rydz-Smigly, the commander-in-chief and, in 1939, he accompanied the Marshal in the evacuation of the government to Romania. While his father served in General Anders’ army, Jack and his mother stayed in Poland, living in Warsaw and later in Siewierz, near Sosnowiec. In 1946 the family left Poland and were reunited in Great Britain. Kanski senior later became a judge with the United Nations. Jack was educated at Mayfield College in Sussex and then studied medicine at the London Hospital Medical College qualifying MB, BS in 1963. He worked as a house officer at the London from 1963 to 1964, a senior house officer at the Western Ophthalmic Hospital in 1965, a registrar at the Westminster Hospital from 1965 to 1966, a senior registrar in the retinal unit at Moorfields Eye Hospital from 1966 to 1970 and then returned to the London as a senior registrar from 1970 to 1973. In 1974 he was appointed consultant surgeon in the Prince Charles Eye Unit at the King Edward VII Hospital in Windsor where he remained until retiring in 2000. He built the unit into a world-class teaching hospital that attracted ophthalmic trainees from all over the world and he made a point of encouraging medical students from Poland. Although not trained in paediatric ophthalmology, he developed a system of care for dealing with the ocular problems of children suffering from idiopathic juvenile arthritis. He ran a large trial on the treatment of uvietis in the young and carried out many studies on the management of vision-threatening complications. In 1984 he published *Clinical Ophthalmology: a systematic approach* (London: Butterworths, 1984) in which he put to use much of the material he had created (with the help of his wife) as audio cassettes with slides since his registrar days. The book was to become recognised as one of the most important works on the subject and, forty years later, is now being republished in a 10th edition. Its publication was to be followed, over the next 25 years, by more than 30 books covering all aspects of ophthalmology. His works were noted for their lucidity and the quality of the illustrations. The author of numerous scientific papers, he was also keen to disseminate his findings by attending conferences and contributing significantly to ophthalmological education worldwide. He was invited to give the first ever keynote lecture at the World Congress of Paediatric Ophthalmology and Strabismus (WCPOS) in Barcelona in 2009. In 2013, WSPOS established the Kanski medal, which is awarded at every WCPOS to an outstanding contributor to the care of children with ocular disease but who was not a paediatric ophthalmologist by training. His contribution to the field of ophthalmology cannot be overstated. Outside medicine he was fascinated by history, especially that of his native and adoptive countries. He published an outline histories of Poland and England, one book on major figures in European history and one on military commanders in the second world war. He also enjoyed reading, swimming, eating oriental food, and watching films. He married Valerie Ann née Shannon on 3 September 1976 and she survived him when he died of pancreatic cancer at home in Gerrards Cross on 5 January 2019 aged 79. As one of the most popular contemporary authors of ophthalmic texts, Mr. Jack J. Kanski will be sadly missed, but his work will live on indefinitely. Ophthalmologists, optometrists, and vision professionals around-the-world will remember Mr. Kanski forever, for his priceless contribution to the field of ophthalmology. Financial support and sponsorship https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6376827/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8027811/ https://www.escrs.org/eurotimes/jack-kanski-1939-2019