| 2012-present | University of Toronto, Institute for Health Policy, Management and Evaluation | Cross Appointment |
| 1997-present | University of Toronto, Dept. of Mechanical and Industrial Engineering | Professor |
| 2006-26 | Institute for Clinical Evaluative Sciences (ICES) | Adjunct Scientist |
| 2016-17 | University of Toronto, Dept. of Mechanical and Industrial Engineering | Research Leave |
| 2007-17 | University of Toronto, School of Public Policy & Governance | Cross Appointment |
| 2006-12 | University of Ottawa, School of Management | Adjunct Professor |
| 2008-09 | University of Toronto, Dept. of Mechanical and Industrial Engineering | Research Leave |
| 2003-04 | University of Toronto, Dept. of Mechanical and Industrial Engineering | Associate Chair – Strategic Development |
| 2001-02 | University of Toronto, Dept. of Mechanical and Industrial Engineering | Sabbatical Leave |
| 1984-2002 | University of Toronto, Dept. of Computer Science | Cross Appointment |
| 2001, Sept. | Monash University, Australia | Visiting Professor |
| 1993-2000 | University of Toronto, Dept. of Biomedical Eng. | Cross Appointment |
| 1999, July | Monash University, Australia | Visiting Professor |
| 1996-98 | University of Toronto, Dept. of Mechanical and Industrial Engineering | Associate Chair – Undergraduate Studies |
| 1986-97 | University of Toronto, Dept. of Industrial Eng. | Associate Professor |
| 1994-95 | University of Toronto, Dept. of Industrial Eng. | Sabbatical Leave |
| 1990-93 | University of Toronto, Dept. of Industrial Eng. | Associate Chairman – Graduate Studies |
| 1989-93 | University of Toronto, Dept. of Industrial Eng. | Co-ordinator of Graduate Studies |
| 1984-88 | University of Waterloo, Management Science | Adjunct Professor |
| 1987 | University of Toronto, Dept. of Industrial Eng. | Sabbatical Leave |
| 1981-86 | University of Toronto, Dept. of Industrial Eng. | Assistant Professor |
| 1978-80 | University of Waterloo, Faculty of Mathematics | Assistant Professor |
| 1971-78 | University of Waterloo, Data Processing Dept. | Systems Analysis |
| 1973-77 | University of Waterloo, Faculty of Mathematics | Adjunct Lecturer |
