Dr. Trainor has a general practice in Listowel, which he established after graduating from the Faculty of Dentistry at the University of Toronto. He is a Fellow in The Pierre Fauchard Academy, the International College of Dentists, the Academy of Dentistry International and the American College of Dentists, as well as International Congress of Oral Implantologists. Dr. Trainor is in his third term on RCDSO Council as the elected representative of District #7. During his last term, Peter served as Vice President of RCDSO on the Executive Committee.

He also represented RCDSO on the Board of the Canadian Dental Regulatory Authorities Federation. He and his wife, Sara, have three children and four beautiful grandchildren. Peter and his wife live on an active farm and share a fondness for horses, as well as equestrian sports. His wife, Sara, shows in dressage and Peter competes in combined driving.