From the time we are children, we are taught to say "thank you" and "I'm sorry." These communications are central to many social interactions, and the failure to say them often leads to conflict in relationships. Research has documented that, alongside the impact they can have on relationships, apologies and thanks can also impact material outcomes as small as restaurant tips and as significant as settlements of medical malpractice lawsuits. But, it is trivial to utter the words; how can such "cheap talk" carry so much value? In this article, we propose a "responsibility exchange theory" that explains why these communications are not costless, and which draws connections between four forms of communication that have not previously been connected: thanking, apologizing, bragging, and blaming. All four of these communications relay information about credit or blame, and thus introduce image-based costs and benefits for both the communicator and the recipient of communication: Each of the four communications involves a tradeoff between appearing competent and appearing warm. By formalizing these social psychological insights with a utility-based approach to modeling communication, and by applying game theoretic analysis, we offer new insights about social communication. We test several of the model's novel predictions about strategic communication in two experiments: The first involves hypothetical choices in a scenario study, and the second involves real choices in a live interaction. We end with a discussion of the theory's place in the literature and consider extended predictions and applications as examples of future directions for research. (PsycINFO Database Record (c) 2019 APA, all rights reserved).