Dr. Hirdes played an integral role in the development, evaluation and implementation of the interRAI famil of assessment systems, which has become a Canadian standard for assessing the needs of persons wit complex health problems across the continuum of health care. He developed novel decision support tool that are in widespread use in Canada and internationally to inform clinical practice, policy development resource allocation and quality measurement in home care, nursing home, and mental health settings Hirdes' contribution to improving the quality of health care for vulnerable Canadians was recognized with the Queen Elizabeth II Diamond Jubilee Medal.