Costless pre-play communication has been shown to effectively facilitate within-group coordination. However, in competitive coordination games, such as rent-seeking contests, better within-group coordination leads to more aggressive competition and lower efficiency. We report an experiment in...

Costless pre-play communication has been found to effectively facilitate coordination and enhance efficiency in games with Pareto-ranked equilibria. We report an experiment in which two groups compete in a weakest-link contest by expending costly efforts. Allowing intra-group communication leads...