We study the emergence of conventions in dynamic networks experimentally. Conventions are modeled in terms of coordination games in which actors can choose both their behavior and their interaction partners. We study how macro-level outcomes of the process in terms of Pareto-efficiency and heterogeneity depend on initial conditions. Moreover, we examine the underlying processes at the microlevel. Predictions are derived from a game-theoretic model which is applied to our experimental conditions by means of computer simulation. The results provide mixed support for the macro-level hypotheses, and indicate possible directions to improve the model at the micro level.