This how-to book provides a step-by-step guide to the constituent practices and processes needed to produce a sustainability report, structured around the Global Reporting Initiative's Sustainability Reporting Process. It is written by the first GRI Certified training providers in the UK, who also produced the first GRI Certified Training course to be accredited by the Institute of Environmental Management & Assessment (IEMA). This book will show you: * how to produce a business case, develop action plans, secure leadership over process and people, and how to generate cross functional buy in * how to do stakeholder engagement, materiality and assurance, and how to collect quality data * how to plan and prepare to report, how to finalise and disseminate a report, and how to apply and manage the GRI Materiality Matters Check. The authors also provide invauable tips on on how to write a report, and how to position it on media platforms for both dissemination and feedback. In short, this book is a masterclass on precisely the things that individuals and organisations need and want to know to set up or improve the quality of their reporting processes, and to write effective reports. This book will also enable stakeholders with a professional, personal or academic interest in reporting to learn how to evaluate a report -- an essential skill for report writers too.