Over the years, ECHA has published a wide range of information and tools to help registrants to prepare high-quality dossiers. ECHA is also actively communicating to companies about deficiencies in their dossiers through screening campaigns and formal measures such as compliance checks. This web section collects the various information sources and tools in a one-stop shop, where registrants can easily find concrete support to improve their dossiers. Companies are encouraged to consult this information before updating the dossier, or submitting a new one, to find out what ECHA expects from a good-quality dossier.