The Caribbean area as defined here includes the Greater Antilles, Lesser Antilles, the northern boundary of South America, and Central America (Fig. 1); it spans approximately 7,800 km in an east-west direction and 3,900 km in a north-south direction. Although the geology of this region should be considered along with that of Mexico and the Gulf of Mexico, these areas form separate chapters in this book. This chapter is in part a condensation of numerous contributions prepared for the synthesis volume on the Caribbean region by Case and Dengo (1989). Further details are available in that book. Modern geological interest in the Caribbean has centered on its Cretaceous to Recent orogenic belts that resulted from plate interactions between North and South America. The Caribbean is the site of America’s most extensive Cretaceous and Cenozoic oceanic-continental tectonic zone and has (along with the Aleutians) its only real island arcs. It has the majority of the active volcanic centers of the New World and a major share of the destructive earthquakes. The goal of the Caribbean geologist is to reconstruct the history of a minor “plate” whose extensive internal deformation belies the strict application of this term. This “plate” has been broken and twisted within the jaws of three major plates (Farallon, North America, and South America), whose relative motions have changed dramatically from Jurassic to Recent time. However, the average motion among the three plates since the middle Cretaceous has been one of roughly east-west compression, and the aim of this paper is to place the geologic history in the context of these changing major plate motions.