This chapter is organised in three parts. The first section discusses structural features of bureaucracy and how these determine the character of authority within bureaucracies. The second section discusses issues concerning the functioning of bureaucracy and authority, including decision-making, discretion, hierarchies, communication and power. The study of the functioning of bureaucratic organisations will make clearer how the structural properties of bureaucracy are interrelated. The third section turns to the critique of bureaucracy and debates surrounding reforms of public administration.