This meta-analysis examines the relationship between information sharing (IS) and team performance, cohesion, decision satisfaction, and knowledge integration. Results from 72 studies (total groups = 4,795; total N = 17,279) show that IS positively predicts team performance across all levels of moderators. The relationship is moderated by the representation of IS (uniqueness or openness), performance criteria, task type, and discussion structure by uniqueness. Three factors—task demonstrability, discussion structure, and cooperation—enhance IS, while member redundancy factors—information distribution, informational interdependence, and member heterogeneity—detract from IS. IS is defined in two ways: uniqueness (sharing information not commonly known) and openness (broad information sharing). Uniqueness is more strongly related to team performance than openness. IS also positively predicts cohesion, member satisfaction, and knowledge integration. Performance criteria moderate the IS–performance relationship, with IS most strongly related to subjective measures, followed by decision effectiveness and objective measures. Task type and discussion structure also moderate the relationship. IS predicts performance more strongly on intellectual hidden profile tasks than on nonhidden profile or judgmental tasks. Structured discussions enhance the impact of unique IS on performance. IS is enhanced by task demonstrability, structured discussions, and cooperation. Conversely, member redundancy factors reduce IS. The study highlights the importance of IS in team decision-making and the factors that influence it. It suggests that teams with less knowledge redundancy share less information, even when it is critical. The findings support the idea that IS is a key driver of team performance, though the relationship is moderated by various factors. Future research should explore the interplay between uniqueness and openness in IS and the impact of team virtuality and boundaries on information sharing. The study underscores the need for interventions to mitigate the member redundancy effect and enhance IS in teams.This meta-analysis examines the relationship between information sharing (IS) and team performance, cohesion, decision satisfaction, and knowledge integration. Results from 72 studies (total groups = 4,795; total N = 17,279) show that IS positively predicts team performance across all levels of moderators. The relationship is moderated by the representation of IS (uniqueness or openness), performance criteria, task type, and discussion structure by uniqueness. Three factors—task demonstrability, discussion structure, and cooperation—enhance IS, while member redundancy factors—information distribution, informational interdependence, and member heterogeneity—detract from IS. IS is defined in two ways: uniqueness (sharing information not commonly known) and openness (broad information sharing). Uniqueness is more strongly related to team performance than openness. IS also positively predicts cohesion, member satisfaction, and knowledge integration. Performance criteria moderate the IS–performance relationship, with IS most strongly related to subjective measures, followed by decision effectiveness and objective measures. Task type and discussion structure also moderate the relationship. IS predicts performance more strongly on intellectual hidden profile tasks than on nonhidden profile or judgmental tasks. Structured discussions enhance the impact of unique IS on performance. IS is enhanced by task demonstrability, structured discussions, and cooperation. Conversely, member redundancy factors reduce IS. The study highlights the importance of IS in team decision-making and the factors that influence it. It suggests that teams with less knowledge redundancy share less information, even when it is critical. The findings support the idea that IS is a key driver of team performance, though the relationship is moderated by various factors. Future research should explore the interplay between uniqueness and openness in IS and the impact of team virtuality and boundaries on information sharing. The study underscores the need for interventions to mitigate the member redundancy effect and enhance IS in teams.