This publication presents a comprehensive assessment of waste inventory records systems. A variety of circumstances that may require the records to be re-assessed or retrieved is discussed. The implementation of the waste inventory data retrieval process will vary depending on the specific situation in each country, but the basic approach described in this publication will be applicable for those facilities where loss or inadequacy of inventory records are observed. The guidance provided on the waste inventory data retrieval process is based on the experience gained and approaches employed in some Member States, as part of the overall upgrading programme at their storage or disposal facilities.