For over 40 years, the National Library of Medicine's (NLM) Toxicology and Environmental Health Information Program (TEHIP) has worked to organize and to provide access to an extensive array of environmental health and toxicology resources. During these years, the TEHIP program has evolved from a handful of databases developed primarily for researchers to a broad range of products and services that also serve industry, students, and the general public. TEHIP's resources include TOXNET <http://toxnet.nlm.nih.gov>, a collection of databases, including online handbooks, bibliographic references, information on the release of chemicals in the environment, and a chemical dictionary. TEHIP also produces several resources aimed towards the general public, such as the Household Products Database <http://hpd. nlm.nih.gov>, which helps users explore chemicals often found in common household products, and Tox Town <http://toxtown.nlm.nih. gov>, an interactive guide to commonly encountered toxic substances, health, and the environment. This paper introduces some of NLM's environmental health and toxicology resources.