Sustaining finite public resources presents a dilemma between acting in self-interest for present benefit versus working toward long-term collective gain. Given gratitude's links to prosociality and self-control, the present studies investigated whether gratitude would promote sustainable resource extraction under conditions of rapidly depleting resources. In Study 1 (N = 155), participants were randomly assigned to experience an emotional state (gratitude or neutral) prior to playing a resource dilemma game in which the common pool was manipulated to indicate either a sustained or depleting resource status. Neutral participants increased their point taking when the pool was depleting compared with when it was sustained; however, this pattern was not observed for grateful participants. Study 2 (N = 224) replicated these findings while also showing the effect of gratitude to be distinct from happiness. These findings show that gratitude, as opposed to a general positive emotional state, buffers against overtaking in resource dilemmas and suggests that this emotion may be useful in promoting sustainable behavior. (PsycInfo Database Record (c) 2021 APA, all rights reserved).