For more than a decade, the Australian Institute of Health and Welfare (AIHW) has been undertaking data development, and assisting other organisations with related activities. In doing so, the AIHW has developed a body of expertise in data development. Much of this experience has been distilled into 'A guide to data development'. The guide covers the basics of data development and the steps to follow when developing data. It outlines sound data development practices that incorporate the necessary steps to produce high-quality data that meet the needs of all users of the data and attract the necessary level of agreement on content and authority behind the data specifications. The document promotes the role of metadata in describing data and the use of data standards to improve consistency in data recording where data consistency and comparability is required.