Legislatures tend to serve a common purpose and perform a set of core functions, although legislative organization and activities generally reflect the existing political culture of a state. While lawmaking and oversight consume a significant amount of time and resources, constituent representation is the primary responsibility of state legislators. Elected officials and their staffs spend the vast majority of their time answering constituent requests through casework and other forms of constituent service.

The structure and composition of state legislatures have changed dramatically in the last forty years. The rise of professionalized legislatures has significantly increased the power of legislatures and the authority of individual legislators. It also has resulted in a significant increase in career-oriented legislators. This contributes to variation in legislative composition and organization. As the degree of professionalization has increased, however, public approval of legislative activity has decreased. Thus, despite improving efficiency and effectiveness, state legislatures remain unpopular with the American public. For this reason, states with highly professionalized legislatures also tend to have term limits in place for incumbents. These states often provide for direct citizen influence in the form ballot initiatives and referendums as well.