• World Bank, UNAIDS, and World Health Organization, “Global Health in the Age of AIDS: Challenges of Global Governance,” World Bank, Washington, D.C., November 28, 2006, In Commemoration of World AIDS Day.
• The Public Health Agency of Canada, Keynote Address: “The Role of Law in Advancing the Public’s Health.” Canadian Conference on the Public’s Health and the Law, Toronto, November 5, 2006.
• University of Wales, Welsh Department of Health, and Faculty of Public Health of the Royal Colleges of Physicians, The Archie Cochrane Memorial Lecture “Law and the Population’s Health: Finding the ‘Common Good’ in Public Health Policy,” National Museum of Wales, Cardiff, November 2nd 2005.
• European Union Presidency: Tackling Health Inequalities: Governing for Health Summit, Queen Elizabeth II Conference Centre, London, 17-18 October 2005.
• The World Congress on Public Health Law and International Congress on Medical Law, Keynote Address, Seoul, Korea, August 17-21, 2005.
• Lecture Series in Public Health Law and Ethics, New Zealand:

- University of Auckland and Ministry of Health, “Contemporary Issues in Public Health Law,” Keynote Address, April 21, 2005.

- New Zealand Centre for Public Law, Victoria University of Wellington, “Biosecurity: From SARS and Influenza to Bioterrorism,” Public Lecture, April 26, 2005.

- University of Otago, “Genomics in Public Health,” Dunedin, April 28, 2005.

• London School of Hygiene and Tropical Medicine, “Legal Foundations of Public Health Law and its Role in Meeting Future Challenges,” London, February 16, 2005.
• American College of Legal Medicine, Cyril Wecht Distinguished Lecture in Legal Medicine, “Is There Space for the ‘Public Good’ in Health Policy?,” San Diego, CA, March 5, 2005.
• World Health Organization, International Human Rights Law & Mental Disability: Liberty, Dignity, Equality, Entitlement, Geneva, Switzerland, 12 July 2004.
• National Health Law Conference: A Tribute to Prof. Bernard Dickens, University of Toronto, Canada, January 22nd, 2004, Keynote Address: “Ethical and Legal Challenges Posed by SARS: Implications for the Control of Severe Infectious Disease Threats.”
• Nuffield Trust, Queen Elizabeth II Center, London, England, January 8th, 2004 (Commemorating the 150th Anniversary of the Public Health Act 1848), Keynote Address: “Health of the People: The Highest Law.”
• Australian National Centre for Law and Public Health, Melbourne, Australia, July 22nd, 2003 (Commemorating the Inauguration of the Australian National Centre of Public Health Law), Keynote Address: “Law and Ethics in Population Health.”
• World Health Organization, When Terrorism Threatens Health: How Far are Limitations on Human rights Justified?, Geneva, Switzerland, March 25, 2002. (This address was also delivered to the Centre for Socio-Legal Studies, Oxford University, June, 2002).
• Keynote Address for the International Conference on Electronic Patient Records in Medical Practice, 7-10 October 1998, World Trade Center, Rotterdam, The Netherlands.
• Nancy Weaver Emerson Medical Ethics Lecture, Duke University, November 4, 1998, Durham, North Carolina.
• First Distinguished Robert H. Levi Lecture in Bioethics and Public Policy, the Johns Hopkins University, April 24, 1998, Baltimore, Maryland.
• Keynote Address for the Global Forum on HIV, Human Rights and the Law, October 1997, Delhi, India.
• Workshop of Ministers of Health and Ministers of Justice from the Asian Region, AIDS Legislation, November 1996, Beijing, China.
• Special Olympics, Should Difference Make a Difference? Yale University School of Law. Hartford, Conn., April 1995.
• Commencement Address. State University of New York. Brockport, New York, May 1994.
• Keynote Address for the Inauguration of the Health Law Institute. The University of Wales, Cardiff, March 1993.
• US-USSR AIDS Symposium. Face-to-face meeting of scientists under the auspices of the governments of the US and USSR, the Institute of Medicine, and the Soviet Academy of Sciences. Washington, DC., September, 1990.
• Co-Chair. London '89: Second International Conference on Health Law and Ethics. London, England, July 16 - 21, 1989.
• Psychiatry Without Asylums. 2000th Anniversary Celebration of the University of Bologna. Italy, October 20 - 22, 1988.
• Human Rights, Children and AIDS. General Assembly of the United Nations. New York, April 15, 1988.
• Japanese Psychiatric Assn/International Academy of Mental Health and Law. Human Rights in the Japanese Mental health System. Kyoto, Japan, January 30, 1987.
• World Federation for Mental Health. Human Rights in Mental Health. London, England, June 1986.
• International Federation of Human Rights, UNESCO. Racial Determinants in Immigration Policy. Paris, France, March 1984.
• Royal Society of Medicine, Section of Neurology. Legal and Ethical Issues. London, England, May 6, 1982.
• Law and Psychiatry III. Special edition of the Fourth International Congress on Law and Psychiatry. Pembroke College, Oxford University, England, July 19-22, 1979. Selected papers published in the International Journal of Law and Psychiatry 1980; 3(1):1.
• Social impediments to the phasing out of institutions in Europe. Delivered to the Italian Mental Health Services Conference. Psichiatri E Buon Governo. Arezzo, Italy, October 28 - November 4, 1979.
• The social and political use of psychiatry in an international perspective. Delivered to the Polish Psychiatric Association Congress on Psychiatric Legislation. Warsaw, Poland, June 3, 1978.
• A critique of the proposed Mental Health Act of Poland. Delivered to the Second International Congress of Law and Psychiatry. Toronto, Ontario, Canada, Feb. 24, 1978.
• Mental handicap hospitals and their alternatives. Delivered to the Royal Society of Health. London, England, Oct. 1977.