On behalf of the Conservation Law Foundation, this report, prepared by the Applied Economics Clinic (AEC), investigates how well Massachusetts' energy efficiency programs are reaching under-served communities and hard-to-reach families. In 2017, Massachusetts' "Mass Save" energy efficiency programs ranked number one in the annual efficiency scorecard produced by the American Council for an Energy-Efficient Economy (ACEEE) for the seventh consecutive year. Mass Save's ranking is not, however, a good indicator of whether or not low-income households are getting the services they need. At present, it is not possible to answer this question completely because Mass Save program administrators have access to - but do not include in publicly available statistics - information regarding low-income households, under-served communities and hard-to-reach families. Working with limited data, AEC found that there are substantial differences in energy savings among Massachusetts' towns, and lower-income communities are receiving lower efficiency savings. This report presents maps and other figures showing differences in efficiency savings, income, and other community characteristics like language abilities and renter status for both Massachusetts towns and neighborhoods within Boston.