Since 1948 the Oshawa Clinic has been providing quality health services to families in the Durham Region and over this period, the group has grown into the largest medical group practice in Canada (currently 110+ doctors). The Oshawa Clinic originated from a partnership formed in 1927 by Dr. Grant Bird and Dr. Oscar G. Mills who had graduated together from the University of Toronto in 1921. Dr. Bird made many visits to the Mayo Clinic in the United States bringing back new surgical techniques along with a vision of establishing a medical group practice in Oshawa. In 1930 they were joined by Dr. W.S. Millman who specialized in Diagnostic Radiology and in 1934 by Dr. James R. Bayne who developed the specialty of Paediatrics.
During the busy years of 1939 to 1945 when there was a severe shortage of doctors in Oshawa, this medical group became known as the Oshawa Clinic and plans were made for a new building. The "new" Clinic opened at the corner of King Street and Charles Street in Oshawa on December 1, 1948.
In 1962, a 30,000 square foot wing was added at the south side of the original property.
In 1948 the population of Oshawa was 25,000 and the Oshawa General Hospital had about 150 beds. In response to the rapidly increasing population, the Clinic continued to add medical staff, hired a business administrator and developed improved facilities for laboratory, X-ray, physiotherapy, pharmacy and medical records. In 1962, a 30,000 square foot wing was added at the south side of the original property. With continuing growth in the area, the Oshawa Clinic partners decided to embark on a major expansion and on May 19, 1971, opened the eight storey tower to allow the group to grow to approximately 40 doctors and establish the urgent care clinic. In 1985 the laboratory, front lobby and urgent care clinic were enlarged and in 1987 the three storey west wing building was added to the complex.
The Oshawa Clinic has continued to expand to over 110 physicians. During this period, the group recognized that much of the residential growth in the Durham Region was east of Oshawa in the Courtice area. This area was highly underserviced by doctors and they wanted to better serve the needs of the Courtice residents. In doing so, they built a first class medical facility called the Courtice Health Centre, which opened on April 12, 1999, and which is home to 22 family physicians, diagnostic imaging and laboratory services, dental centre, hearing testing, rehab services and a number of programs operated by Lakeridge Health Corporation.
With the success of the Courtice Health Centre, the group decided to build an identical facility on 2 acres of land in North Oshawa, close to the new University (University of Ontario Institute of Technology). The new Taunton Health Centre opened in May 2006 and is home to 16 family doctors, walk-in clinic, plus a wide range of diagnostic and treatment services.