Bringing energy efficiency to our nation’s building stock is an attractive triple bottom line proposition, and a critical one—for addressing global climate change, improving environmental quality and health, and delivering cost savings to owners and tenants. Although markets for retrofitting commercial properties and single family homes are developing, many low-income people are still waiting on the sidelines to partake in benefits. This trend is particularly worrisome because the least fortunate are more likely to live, attend school, and work in older, less energy-efficient buildings; as a result, low income households consume about one quarter more energy per square foot of living space than their higher-income counterparts, and a larger share of their paychecks are dedicated to utility costs. Poorer communities’ limited ability to pay for retrofits has caused energy efficiency markets designed for wealthier settings to bypass them. In this context, we at the Low Income Investment Fund (LIIF) interpret the considerable challenge of delivering energy efficiency to low-income families and low-wealth communities as crucial not only for environmental sustainability, but also for addressing social inequality.