Cooperation occurs at all stages of human life and is necessary for small groups and large-scale societies alike to emerge and thrive. This chapter bridges research in the fields of cognitive neuroscience, neuroeconomics, and social psychology to help understand group cooperation. We present a value-based framework for understanding cooperation, integrating neuroeconomic models of decision-making with psychological and situational variables involved in cooperative behavior, particularly in groups. According to our framework, the ventromedial prefrontal cortex serves as a neural integration hub for value computation during cooperative decisions, receiving inputs from various neuro-cognitive processes such as attention, affect, memory, and learning. We describe factors that directly or indirectly shape the value of cooperation decisions, including cultural contexts and social norms, personal and social identity, and intergroup relations. We also highlight the role of economic, social, and cultural institutions in shaping cooperative behavior. We discuss the implications for future research on cooperation.