This dissertation examines the interaction between voters and party elites in parliamentary democracies, particularly those with multiparty governments. In the first half of the dissertation I focus on individual party supporters and explore their reactions to coalition policymaking. I develop a heuristic model that explains voters' preferences for coalition governance and the consequent impact of their preferences on voting behavior. I contend that party voters' preferences for coalition governance are associated with two simple heuristics: cabinet membership and their own ideological locations relative to parties in a coalition on the left-right policy spectrum. I find that party supporters who perceive themselves to be located between coalition partners are less likely to cast a punishing vote. This is because voters expect that policy compromise essentially brings cabinet parties closer to their own ideal points. In the second half of my dissertation, I derive a behavioral implication from the theory regarding the collaborative behavior of party elites. I argue that rational politicians should be able to predict the potential cost of coalition participation by gauging the size of ideological interior voters (i.e., party supporters located in between a pair of parties) they share with other parties, and that they can respond to this information by acting strategically. Specifically, political parties are more likely to cooperate with one another when they share more interior supporters than when they do not. This is because parties in such a situation face a lower cost of collaboration if they chose to partner with each other. I then examine this implication empirically by using data on parliamentary speeches and coalition partnerships. The empirical investigations show results that are consistent with my argument. I find party elites to be less likely to engage in lengthy floor debates on government policies and to be more likely to govern together when they share more interior voters. Taking all these findings together, this dissertation enhances our understanding of citizens' preferences for collective policymaking and of the connection between voters and political elites in parliamentary democracies.