We incorporate elements of a social-constructionist viewpoint into social-exchange theory and show how mutual dependence can produce expressive behavior in the form of gift giving. Exchange networks typically create varying degrees of mutual dependence in component dyads, and greater mutual dependence produces more frequent exchange. We propose that over time, frequent exchange generates an expressive relation and unilateral, token gifts are an indicator of emerging expressiveness in an exchange relation. To experimentally test the impact of mutual dependence on token gift giving, two focal actors, each with one alternative partner, attempted to negotiate an exchange across multiple opportunities. The results indicate that high compared to low mutual dependence increased gift giving, while also enhancing the attitudinal commitment to and perceived closeness of the relation. Consistent with the theory, these effects of mutual dependence were indirect, operating through the frequency of exchange. Broadly, the paper has theoretical implications for how and when endogenous processes in dyads generate certain micro-to-macro effects.