The purpose of this report is to provide a comprehensive analysis of domestic heavy oil resources. Toward this end, the authors have constructed a comprehensive, systematically organized database of the general characteristics of the significant heavy oil fields in the contiguous 48 states, and then used this database to describe domestic in-place heavy oil resources and to analyze their recovery and production potential, considering both technical and economic factors. Section II describes the database. Section III discusses the geographic and geologic distribution of heavy in-place oil resources in the contiguous 48 states, the gross reservoir and fluid characteristics of these resources, and previous cumulative production and current reserves of heavy oil. Section IV analyzes the technology and economics of domestic heavy oil recovery. Section V presents three scenarios for domestic heavy oil production in the year 2000.