Five statistical software packages for epidemiology and clinical trials are reviewed. The five packages are EPI INFO, EPICURE, EPILOG PLUS, STATA, and TRUE EPI-STAT. Only DOS versions of these packages are compared and rated (Windows versions are discussed but not rated). Although the packages differ in their target audiences, interfaces, capabilities, and approaches, they are examined according to criteria that are of most interest to epidemiologists, biostatisticians, and others involved in epidemiologic and clinical research. A general discussion with recommendations follows the review of the statistical packages. © 1998 Taylor & Francis Group, LLC.