The paper identifies the quality assurance and quality control (QA/QC) objectives that must be met to creat a comprehensive and accurate emissions inventory and summarizes the QA/QC plan specifically designed for the 1985 inventory to meet these objectives. The data quality objectives, priorities, and constraints for the collection of the 1985 inventory data are reviewed. QA/QC checks of both state data and the completed inventory are discussed. Guidelines for data processing, documentation, and the calculation of data quality indicators are reviewed. A fundamental objective of the National Acid Precipitation Assessment Program (NAPAP) research program is the location and quantification of natural and anthropogenic emissions that may contribute to acid deposition. To achieve the objective, NAPAP's Task Group and Emissions and Controls is conducting a multi-year research effort to develop an accurate and comprehensive inventory of 1985 emissions from sources thought to be important in acid deposition processes. Most of the 1985 emissions data for the inventory are being collected and analyzed by state air pollution control agencies and the U.S. EPA.