We consider the credibility, persuasiveness, and informativeness of multidimensional cheap talk by an expert to a decision maker. We find that an expert with state-independent preferences can always make credible comparative statements that trade off the expert's incentive to exaggerate on each dimension. Such communication benefits the expert—cheap talk is “persuasive”—if her preferences are quasiconvex. Communication benefits a decision maker by allowing for a more informed decision, but strategic interactions between multiple decision makers can reverse this gain. We apply these results to topics including product recommendations, voting, auction disclosure, and advertising. (JEL D44, D72, D82, D83, M37)

Two players with common interests exchange information to make a decision. But they fear scrutiny. Their unencrypted communications will be observed by another agent with different interests who can object to their decision. We show how the players can implement their ideal decision rule using a back-and-forth conversation. Such a subversive conversation reveals enough information for the players to determine their best decision but not enough information for the observer to determine whether the decision was against his interest. Our results show how conversations can maintain deniability even in the face of leaks, hacks, and other public exposures.