In service of the broad aim of understanding the politics of public policy, thisbook pursues three interrelated goals.The first goal—tackled in Part I—is to spend some time thinking aboutthe normative foundations of policymaking. That is, to ask questions like,“What are the proper goals of public policy?” In so doing, we will discoverhow difficult it is to come up with a coherent, unified, normative frameworkto motivate policy decisions. We will arrive at one limited version of such aframework, but we will also see that the ambitious program of formulating abroad conceptualization of the public interest that everyone can endorse mightbe a fool’s errand. Nonetheless, along the way we will discover some usefuland provocative ideas that will make our thinking about these issues morestructured and nuanced.The second goal is to think through some fundamental aspects of social lifethat create opportunities for public policy to make the world a better place. Icall these aspects of social life—which are developed in Part II—social dilemmas.These social dilemmas are ubiquitous features of human interaction that giverise to predictably regrettable outcomes. We will discuss ways in which policymight improve those outcomes. The objective, in this part of the book, isto develop some habits of mind that let you see the world through a fewanalytical lenses. I believe you will find that once you get used to viewing theworld through the lens of these social dilemmas, you will start to see themeverywhere. This may be a bit depressing, but it is also useful in identifyingopportunities for policy to do good.The third goal is to think seriously and conceptually about the politics. AsI said in the preface, I’m not going to do this by analyzing the politics ofpolicymaking institution by institution. Instead, in Part III, we look at twoclasses of explanations for why governments might not always achieve goodpolicy outcomes. The first focuses on technological constraints—facts about the2 This argument is based on the discussion of the success of cap and trade in curbing sulphurdioxide emissions in Patashnik (2008, Chapter 8).Introduction 5policymaking process that limit the government’s ability to achieve good policyoutcomes even when policymakers are genuinely motivated to do so. Thesecond focuses on incentive constraints. Policymakers are people with their owninterests and concerns. We analyze how some fundamental facts of politics—most especially leaders’ desire to remain in power—interact with political in-stitutions to determine when policymakers have better or worse incentives topursue good policy. We end this part of the book by looking at a bit of evidenceon how the organization of government affects policy outcomes—including anextended discussion of foreign aid policy