The focus of this paper is on Data Quality as it applies to Nutritional Compositional Databases. Quality implies fitness for the purposes for which the data will be used. An appreciation of the requirements of the users of the database is thus a primary determinant of the standards that should be applied during the generation of the data. Most users expect that the compositional data will be representative of the foods consumed by the population being studied and thus Sampling is the first critical element. It is also expected that the data will be analytically sound so the second critical element is Analytical Quality. Finally, the Compilation process involves making judgements about the data to be included and their presentation and in this the users expect that the compilation process will adopt to focus on the quality of the data that will meet their needs. The integration of these elements during the production of data for inclusion in the database will be advocated. Finally, there follows a discussion of how best to present data quality in a database so that the users can use the database appropriately and effectively.