A central assumption of democratic government is that representatives know important things about the citizens they represent. Successful governments wish to know what their citizens want them to do now and in the future. Politicians, political staffers, and political advisors seek to know the needs and political preferences of their voters and constituents. In some cases, politicians will seek to know the behavior of citizens, and how it is related to government policy. Central to this assumption related democratic representation is another assumption: politicians have available the information required to learn about citizens.