Does it seem somewhat ironic that as healthcare stakeholders are working around the globe to use real-world evidence (RWE) to improve patient outcomes, we don’t have common definitions or language? At IMS Health, we wanted to help with that. Welcome to the RWE Dictionary. Our goal is to provide an easy-to-use tool to support a common understanding of RWE. We are not trying to reinvent the wheel – well-established definitions have been adapted – but we have also clarified definitions for terms that are evolving. We hope you find this to be a valuable and useful resource in your RWE pursuits.