Bureaucracies grow due to structural and political factors. Structurally, bureaucracies expand to manage increasingly large organizations and implement complex policies. Politically, elected officials and bureaucrats have incentives to increase the size and scope of bureaucracies. While bureaucracies can promote efficiency and policy goals, their growth must be controlled through oversight, statutory constraints, and balancing ex ante rules with ex post review. Effective political leadership and democratic values are also important to constrain unwarranted bureaucratic expansion.