His varied career has included positions in both juvenile and adult corrections, as a deputy sheriff, and as a private detective. He has directed a halfway house for drug abusers, a comprehensive drug abuse treatment center, and a private school for emotionally disturbed children. He served as a research associate to the working group on substance abuse treatment for the President's Task Force on National Health Care Reform chaired by First Lady Hillary Clinton in 1993. He has held academic appointments as Associate Professor of Health Science at the State University of New York at Brockport, Professor of Health Education at Southern Illinois University, Professor of Biology at the Community College of Rhode Island, Professor of Health and Environmental Research at the University of Cologne in Germany, and Associate Professor of Medical Science (Community Health) at Brown University. He has been a visiting lecturer at the University of Rochester, New York State School of Psychiatry, Columbia University's Teachers College and School of Public Health, New England Gerontology Academy, Trinity College (Dublin), Oxford University, German Academy of Public Health, University of Würzburg, and Universidad Complutense de Madrid.