This chapter focuses on pro-environmental spillover processes. It suggests that individuals developing a strong green identity through public and/or private green activism hold a strong motivation also to engage in high-intensity employee green behavior (EGB). The chapter discusses the influence of the perceived organizational context on green employees' willingness and ability to spill over their private green activism to their workplaces. It shows that individuals who hold a strong green identity do engage in high-intensity EGB even in exclusionary contexts, i.e., in the absence of supportive Green Human Resource Management (GHRM) tools and structures. The chapter also presents the results from a qualitative study on green employees and their spillover experiences at work. It provides implications for the design and implementation of GHRM tools in view of the needs and preferred strategies of 'green' employees for their green initiatives at work.