The current climate crisis represents a tangible threat to individual and collective well-being. There are numerous barriers in navigating climate challenges, including misinformation, low educational resources, and counter-intuitive policies. The establishment and maintenance of environmental resilience is key in overcoming these barriers and promoting greater pro-environmental behaviors. Positive psychological theory, like the 24-character strengths model, offers multiple pathways of transforming how individuals and communities sustain pro-environmental habits. Zest, a character strength defined by the ability to access and sustain high levels of enthusiasm, vitality, and vigor, is an undervalued resource in promoting ecological prosperity. This chapter synthesizes theory and empirical evidence to highlight how zest can stimulate ecological well-being. Notably, this chapter evaluates the underlying features of zest, as a character strength, and how zest processes can help activist shareholders maintain and enhance their commitment to sustainable living, especially during times of adversity and threat. Methodologically, this chapter will present a theoretical model of pro-environmental behaviors highlighting the impact of zest. The chapter will also discuss how a balanced model of emotion regulation, centering zest dimensions, can increase activist shareholders’ commitment to collective action, support activist shareholder self-care, and build enduring personal resources, when working in the context of social and political adversity.