This present research maintains that collectivism facilitates the process of addressing large-scale collective action problems, such as the COVID-19 pandemic and climate change crisis. Addressing large-scale collective action problems requires the intervention of an authority to mobilize a large proportion of individuals to engage in community-benefitting behaviors. In Chapter 1, I propose a theoretical framework that describes the ways in which collectivism align with the characteristics of addressing large-scale collective action problem. Specifically, I propose three psychological mechanisms – other-orientation, susceptibility to social norms, and trust in authority – will explain collectivists’ tendencies to engage in community-benefitting behaviors. In Chapter 2, using the COVID-19 pandemic as a large-scale collective action problem, I test how the three aspects of collectivism predicts greater compliance with people’s likelihood of opting-in to digital contact tracing and wearing a face covering in public (Study 1). Findings show that susceptibility to social norms consistently predict greater compliance with both health preventative measures, while other-orientation does not. Findings also show mixed effect of trust in government, where greater trust only predicts greater likelihood of opting-in to digital contact tracing, as the measure has direct relevance with the government. In Chapter 3, I probe the relationship between collectivism and trust in government further in the context of climate crisis. Across Studies 2 and 3, I analyze two global datasets to show that collectivists have greater pro-environmental intention and support for climate change policies more, in part because they place greater trust in government. In Study 4, I test the causality of trust in government on policy support by asking participants to imagine themselves moving to a new country with a government that differs in their levels of competence and corruption, and test the moderating role of collectivism. Finding show the robust relationship between collectivism and policy support across conditions. Regardless of the levels of a government competence and corruption, high collectivists are still more likely to support climate policies compared to low collectivists. Lastly, I discuss the limitations, boundaries, and future directions of this research in Chapter 4. This research expands our theoretical understanding of collectivism by identifying specific psychological mechanisms that relates to particular behaviors, and highlights the need to leverage collectivism to promote community-benefitting behaviors across different large-scale collective action problems.