This document presents a scoping study for an evaluation of the effects of the California investor-owned utilities’ (IOUs) 2006 – 2008 energy efficiency programs on the commercial & industrial (C&I) markets for high bay lighting (HBL) products.1 It presents a preliminary characterization of those markets based upon secondary research, interviews with program staff, and in-depth interviews with small samples of lighting manufacturers, distributors and installation contractors. The scoping study also summarizes the design and accomplishments of the relevant utility programs. We use the summary market and program information as points of reference for the detailed market effects study work plan, which constitutes the final chapter of the report.