In response to recent calls for more micro-foundation research in corporate social responsibility, this article approaches environmental sustainability from an organizational behavior/human resource perspective. Specifically, this article refines the concept of the environmental workplace behaviors (EWBs), defined here as "work behaviors directed toward the protection or improvement of the natural environment, which may or may not generate value for the organization; these behaviors may be performed by employees situated at any organizational level." EWBs include organization citizenship behaviors for the environment (OCBEs), environmental in-role behaviors (EIRBs), and environmental counterproductive workplace behaviors (ECWBs). Furthermore, the article distinguishes between low-intensity and high-intensity EWBs and discusses the importance of constructs such as trust and power for green employee engagement in EWBs. The article concludes with recommendations for future research and practice in the area of environmental behaviors in organizations.