We investigated the relationship between Theory of Mind (ToM) and communicative cooperation. Specifically, we examined whether communicative cooperation is affected by the ToM ability of one's cooperative partner as well as their own. ToM is the attribution of mental states to oneself and others; cooperation is the joint action that leads to achieving a shared goal. We measured cooperation using a novel communicative cooperation game completed by participants in pairs. ToM was measured via the Movies for Assessment of Social Cognition (MASC) task and fluid intelligence via the Raven task. Findings of 350 adults show that ToM scores of both players were predictors of cooperative failure, whereas Raven scores were not. Furthermore, participants were split into low- and high-ToM groups through a median split of the MASC scores: high-ToM individuals committed significantly fewer cooperative errors compared to their low-ToM counterparts. Therefore, we found a direct relationship between ToM and cooperation. Interestingly, we also examined how ToM scores of paired participants determine cooperation. We found that pairs with two high-ToM individuals committed significantly fewer errors compared to pairs with two low-ToM individuals. We speculate that reduced cooperation in low-low ToM pairs is a result of less efficient development of conceptual alignment and recovery from misalignment, compared to high-high ToM dyads. For the first time, we thus demonstrate that it is not all about you; both cooperative partners make key, independent, contributions to cooperative outcomes. (PsycInfo Database Record (c) 2024 APA, all rights reserved).