David Stanley Precious was chair of the department of oral and maxillofacial sciences and dean of the faculty of dentistry at Dalhousie University, Halifax, Canada. He was born in Ottawa, Ontario on 23 April 1944, the son of John Douglas Precious and Jean Phyllis Precious née Maclaurin. He was raised in Ottawa and attended Glebe Collegiate Institute there and, in 1961, went on to study at Dalhousie University, where he played on the varsity football team. In 1965 he was accepted into the doctor of dental surgery program and graduated in 1969. He immediately joined Dalhousie’s master of science program in oral and maxillofacial surgery, which he completed in 1972. In the same year he received a research grant to study with Hugo Lorenz Obwegeser, the pioneer of modern orthognathic surgery, in Zurich, Switzerland. In 1973, on his return to Canada, he joined the Dalhousie University faculty. In the early 1980s he also trained in cleft surgery with Jean Delaire in Nantes, France. From 1985 to 2004 Precious was chair of the department of oral and maxillofacial sciences, becoming a professor in 1987. In 2003 he was appointed dean of the faculty of dentistry, serving until 2008. Under his leadership, the department of oral and maxillofacial sciences grew to become a leading, internationally recognised clinical and research unit. He realised the importance of subspecialisation and was one of the first chiefs in North America to recruit subspecialists to his department. Dalhousie gained a reputation for excellence in cleft lip and palate surgery, orthognathic surgery, trauma surgery, the management of sleep apnoea, cancer, temporomandibular joint disorders and implantology. For more than 20 years he also travelled extensively abroad to provide free cleft lip and palate surgery to children and to train local practitioners. He delivered more than 250 international lectures and wrote more than 200 peer reviewed publications and abstracts, 15 book chapters and eight books. He served on the editorial boards of four leading national and international scientific journals, including as oral and maxillofacial surgery editor of *Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology*. He was president of the Canadian Association of Oral and Maxillofacial Surgeons, regent of the American College of Oral and Maxillofacial Surgeons, chair of the board of trustees of the International Cleft Lip and Palate Foundation and registrar of the Royal College of Dentists of Canada. He was a fellow of the Academy of Dentistry International, the International College of Dentists, the American College of Dentists, the Royal College of Dentists of Canada and, in 2005, the Faculty of Dental Surgery of the Royal College of Surgeons of England. He received numerous awards, including the American College of Oral and Maxillofacial Surgeons’ Henry Archer Award (in 2005), the Member of the Order of Canada (in 2007), Dalhousie’s A Gordon Archibald Award (in 2009), the Canadian Dental Association’s Medal of Honour (in 2011), the Queen Elizabeth II Diamond Jubilee Medal (in 2012) and honorary degrees from Université Laval (in 2011) and Dalhousie University (in 2013). In recognition of his outstanding service to the profession of dentistry, Dalhousie’s University Medal in Dentistry – an honour he received himself in 1969 – was renamed the Dr D S Precious University Medal in Dentistry in 2012. Outside his professional work, he volunteered in his community. He served on the boards of the Neptune Theatre, Shakespeare by the Sea, Scotia Festival of Music, the Nova Scotia Council on Higher Education and Canadian Parents for French. Precious died on 3 February 2015 in Halifax, Nova Scotia at the age of 70. He was survived by his wife Elizabeth (née Macdonald), whom he married in 1968, and children Susan and Bruce.