Although commercial and industrial energy use accounts for 70% of end-use energy consumption, most marketing studies have focused on consumer response to energy efficiency programs. We study firms in the commercial real estate sector in Stockholm, Sweden, to demonstrate that existing energy efficiency metrics on which certifications such as LEED and BREEAM are based (such as kWh/m2), while easy to obtain, suffer from significant limitations such as floor effects, thus lose their impact over time. Interviews reveal that CFOs focus almost exclusively on profitability, while corporate, government and (I)NGO sustainability mangers focus almost exclusively on energy reduction. Unfortunately, energy reduction may be impossible (and counterproductive) when an organization is growing. In response, we offer energy productivity, conceptualized as output/unit of energy, as an alternative metric. We demonstrate, with data from firms in Stockholm, that it overcomes the limitations of existing measures and produces positive results for firms and society. As a result, it has the potential to function as a measure that CFOs and environmentalists can both embrace. Recommendations for implementation are discussed.