While there has been much interest in recent years in concepts of sequence stratigraphy, this book focuses on stratigraphic units that are, in general, an order of magnitude smaller than sequences. A knowledge of such architectural detail is of considerable significance in the development of detailed, scaled facies models for depositional environments, and is of paramount importance in the efficient design of advanced petroleum recovery projects. This book is the outcome of a SEPM Research Symposium held at the annual meeting of the Society in San Antonio, Texas, April 1989. The intent of the meeting was to bring together modern research on facies architecture, and to apply this research to the investigation of reservoir heterogeneities and production problems.