These guidelines were developed to supplement the Greenhouse Gas Protocol for Project Accounting, published in December 2005 by the World Resources Institute and the World Business Council for Sustainable Development. The chapters in Part I contain background information related to the GHG accounting and quantification procedures described in Part II. Chapter 1 provides an introduction and overview of how these guidelines can be used. Chapter 2 contains information on key concepts necessary to understand and perform the GHG accounting procedures. Chapter 3 provides guidance on special considerations related to project activities that reduce consumption of grid electricity (i.e., energy efficiency and similar project activities).