Systems thinking is thought to facilitate complex decision-making, but relatively little is known about its psychological underpinning. We present three studies that situate a measure of the construct in relation to other dispositional measures that have received more attention in environmental psychology and by testing whether the mindset predicts behavior in a set of novel decision making tasks. In Study 1, we find that systems thinkers tend to believe in scientific consensus, recognize risks posed by climate change, and support policy interventions to address climate change; systems thinking was negatively related to conspiracist and free-market ideation. In Studies 2 and 3 we find that systems thinkers ascribe more value to the natural worldboth in monetary terms as well as on social and ecological grounds. The findings suggest that models of environmental cognition can be improved by measuring peoples' tendency to engage in systems thinking.