Why do an increasingly large number of firms choose to spend their own money and resources to protect the environment beyond the extant regulatory requirements? This article addresses this question by examining the EPA's Green Lights (GL) voluntary program in which a firm's policy makers made an early commitment to limiting greenhouse gases through the installation of energy-e ficient lighting technology in its facilities. Two theoretical perspectives—resource-based theory and neo-institutional theory—are adopted to investigate the contexts by which a firm is encouraged to undertake voluntary environmental actions and evaluate environmental strategies associated with them. Accordingly, the authors focus on two major contexts: market contexts in which a firm adopts voluntary actions as a strategic response to market pressures and to advance competitiveness; and institutional contexts in which a firm takes voluntary postures as a strategic response to institutional pressures, to obtain institutional legitimacy and weaken regulatory scrutiny. The research results partially support both contexts and their associated strategic behaviors.