In the context of these guidelines for national statistics offices and national statistical systems, user engagement is seen as the process of conducting a dialogue with users of official statistics in order to understand their needs and improve the products, services and operation of a statistical organization accordingly. User engagement is central to the impact a national statistical system can have, if not to its very existence. When successful, it can: generate feedback from users that helps statistical organizations to prioritize work based on the statistics the public needs; help ensure that statistics are produced at the right time, in a useful format and are pitched at the right technical level; create opportunities to test experimental statistics and discuss existing statistics to uncover problems such as discrepancies in data; enhance statistical literacy; help build data integrity, trust and a collective sense of ownership of the generation and dissemination of statistics. These guidelines are intended to assist national statistical systems in developing robust and strategic user engagement programs. They consist of a practical mix of instructions, tips and background needed to conduct a dialogue with users and identify what they need and when and through what media they need it.