Voting and committee decisions can be considered the two core elements of the democratic political process. By voting, the members of a constituency determine whom they entrust as representatives with the right to decide on their behalf. By voting, the members of a committee decide which course of action they will take collectively. Hence, voting determines both the input and the output of politics, or in other words, the way in which individuals contribute to a collective outcome. We cannot, however, infer policy from the distribution of individual preferences but in very simple constellations because the chosen policy depends on the interaction between different voters who may have heterogeneous preferences and form different coalitions. These issues have been the main topic of the spatial theory of politics. The role of this chapter in this volume is to give readers some understanding of the broader context of the experiments described in subsequent chapters.