The report is a guide to shape the R&D efforts for the next 5 years for the existing commercial building sector. The Guide identifies the goals for this work, and provides a basis for selecting R&D activities that will help achieve that goal. As the goal of improving the energy efficiency of commercial buildings is shared by many organizations and individuals, the Guide identifies potential partners and presents ways to maintain collaborative efforts. But foremost, this is a guide for DOE program managers and their contractors to refer to in order to develop clear, consistent and coherent R&D programs. The Guide is also a document to show Congress, OMB and others the methodology and logic underlying the recommendations in this guide.