This document summarizes trends in sustainability reporting based on a presentation by Mike Wallace from the Global Reporting Initiative. It finds that 95% of the world's largest 250 companies now report on sustainability, with 80% aligning to GRI standards. Reporting has increased significantly in most countries. However, only 10% of US reports receive external assurance. The presentation outlines growing demand from investors and regulations. It introduces the G4 guidelines which will have profound revisions around materiality, boundaries, and other areas. Reporting is moving towards being more transparent and standard practice globally.