Many valuable collections of academic e-resources are under-utilized simply because potential users are unaware of their existence. The JISC-funded IESR1 based at Mimas2, The University of Manchester, aims to address this by providing a ‘Yellow Pages’ for the academic internet. Its purpose is to capture essential metadata about online publications, resources and research collections in order to encourage greater awareness and use. IESR is a freely accessible source of structured, curated and standardized data about e-resources. It aims to deliver a convenient, central source of information, providing easy access to high-quality learning resources. Data in IESR can be contributed, dis- covered, accessed and re-used in flexible ways by humans or by machines via its machine-readable interfaces.