Sir Harold Delf Gillies OBE FRCS (17 June 1882 – 10 September 1960) was a New Zealand otolaryngologist and father of modern plastic surgery for the techniques he devised to repair the faces of soldiers coming back from the trenches.

[3] He attended Whanganui Collegiate School and studied medicine at Gonville and Caius College, Cambridge, where despite a stiff elbow sustained sliding down the banisters at home as a child, he was an excellent sportsman.

Initially posted to Wimereux, near Boulogne, he acted as medical minder to a French-American dentist, Auguste Charles Valadier, who was not allowed to operate unsupervised but was attempting to develop jaw repair work.

[7] Gillies, eager after seeing Valadier experimenting with nascent skin graft techniques, then decided to leave for Paris, to meet the renowned oral surgeon Hippolyte Morestin.

[8] Gillies became enthusiastic about the work and on his return to England persuaded the army's chief surgeon, William Arbuthnot-Lane, that a facial injury ward should be established at the Cambridge Military Hospital, Aldershot.

[9] The ward rapidly proved inadequate for the increasingly large number of patients in need of treatment, and a new hospital devoted to facial repairs was developed at Sidcup.

[citation needed] Between the wars Gillies developed a substantial private practice with Rainsford Mowlem, including many famous patients, and travelled extensively, lecturing, teaching and promoting the most advanced techniques worldwide.

In 1930 Gillies invited his cousin, Archibald McIndoe, to join the practice, and also suggested he apply for a post at St Bartholomew's Hospital.

[16] In 1951 he and colleagues carried out one of the first modern gender-affirming surgeries, from male to female, on Roberta Cowell,[16] using a flap technique, which became the standard for 40 years.