This chapter presents an overview of the First ISCCP (International Satellite Cloud Climatology Project) Regional Experiment (FIRE) science, covering all the 10 years of the program's existence. Following a workshop held at the National Center for Atmospheric Research in May 1983, a Research Plan was published. According to this plan, the central objectives of FIRE are first “to quantify the capabilities of the current models for large-scale cloud systems and for their effects on radiation, and to obtain the data and understanding necessary to improve these models,” and, second, “to check and improve the interpretation of global statistics on cloud parameters which will be collected by ISCCP. From the beginning, FIRE has been aimed at improving both the large-scale models and satellite cloud retrieval techniques. The five major elements that made up the 1983 FIRE Research Plan are provided. These elements identify a need to focus on two particular cloud types namely, stratus and cirrus, which are singled out because of their strong effects on the Earth's radiation budget.