The U.S. National Library of Medicine's Toxicology and Environmental Health Information Program and the U.S. Society of Toxicology have teamed up to create ToxLearn which is an interactive multi-module learning tool. The purpose of this tool is to provide an introduction to fundamental toxicological principles and concepts, and it does not require any knowledge beyond a basic understanding of biology and chemistry. First-time visitors can click on the "Overview" area to learn more about the modules, which can also be used as an ancillary curriculum to an undergraduate level toxicology course. There are three modules in the course, and while only one is currently available in its entirety, the other two will be added shortly. Each of the modules contains a series of slides and text passages, along with a link to a glossary. This is a tremendous resource, and medical educational professionals and others will find it invaluable.