The Altarum Institute, under contract to the Michigan Department of Transportation (MDOT), currently is engaged in a project called the "Altarum Restricted Use Technology Study." This study, an 18-month effort, seeks to apply restricted use technology to the mandates of MDOT. The major phases of this project are illustrated in Figure 1. Under Deliverable 2.1 of the Work Plan governing the Altarum Restricted Use Technology Study, the Altarum project team is required to produce an unclassified summary and comprehensive written report of Electro-Optical (EO) systems that can potentially address transportation problems. This report presents the fundamental concepts of remote sensing, reviews the categories of civil, commercial and military sensors with their platforms, and discusses potential application areas of EO systems, both in general and those specific to transportation. Together with its companion report on RADAR systems (Deliverable 1.1), this report will provide transportation experts with an overview of current resources and a foundation of potential applications.