Joel A. Harrison, PhD, MPH is a retired epidemiologist who has been writing articles over the past years supporting vaccinations for Every Child By Two, an excellent non-profit founded in 1991. Every Child By Two has changed to Vaccinate Your Family, expanding its mission to include vaccines for people of all ages. You can find Executive Summaries of his previous ECBT articles that hyperlink to the complete articles as well as his brief biography on the archived ECBT Expert Commentaries page (via archive.org). Dr. Harrison has studied and worked in several countries, including Sweden (where he earned his doctorate) and Canada (where he earned a Masters degree). Having experienced both the Swedish socialized health care system and the Canadian non-profit single-payer system, over the past 30 years he has devoted considerable time to studying health economics and health care systems, concluding that, though the Swedish system is excellent, given American culture, he believes that a non-profit single-payer system would be best option for the United States. Dr. Harrison is a long time member of Physicians for a National Health Program.