This chapter lays out some of the basic aspects of how political institutions identify and aggregate the preferences of their constituents. Most democratic political systems use elections to aggregate preferences, and the contours of those political systems are mapped out in a number of voting rights. Voting rights, though, are not unidimensional: they cover everything from casting a ballot to ensuring that ballots are properly weighted to policing the very ability to place alternatives on a ballot in the first place. At the core of all these rights, though, is the recognition that voting should be tied in some way to a person's interest, or stake, in the outcome of an election. Because there are problems with relying upon self-reports of that interest, democratic institutions typically rely upon markers of that interest that allow them to identify and regulate those voting rights. Those markers, though, need to be both accurate descriptions of voter interest (not over- or underinclusive) and manageable.