The public sphere mediates between the "private sphere" and the "Sphere of Public Authority", "The private sphere comprised civil society in the narrower sense, that is to say, the realm of commodity exchange and of social labor." Whereas the "Sphere of Public Authority" dealt with the State, or realm of the police, and the ruling class. The public sphere crossed over both these realms and "Through the vehicle of public opinion it put the state in touch with the needs of society." "This area is conceptually distinct from the state: it 1 a site for the production and circulation of discourses that can in principle be critical of the state." The public sphere 'is also distinct from the official economy; it is not an arena of market relations but rather one of discursive relations, a theater for debating and deliberating rather than for buying and selling." These distinctions between "state apparatuses, economic markets, and democratic associations...are essential to democratic theory." The people themselves came to see the public sphere as a regulatory institution against the authority of the state. The study of the public sphere centers on the idea of participatory democracy, and how public opinion becomes political action.

The basic belief in public sphere theory is that political action is steered by the public sphere, and that the only legitimate governments are those that listen to the public sphere. "Democratic governance rests on the capacity of and opportunity for citizens to engage in enlightened debate". Much of the debate over the public sphere involves what is the basic theoretical structure of the public sphere, how information is deliberated in the public sphere, and what influence the public sphere has over society.

Jürgen Habermas: Bourgeois Public Sphere

main: The Structural Transformation of the Public Sphere

The bourgeois public sphere may be conceived above all as the sphere of private people come together as a public; they soon claimed the public sphere regulated from above against the public authorities themselves, to engage them in a debate over the general rules governing relations in the basically privatized but publicly relevant sphere of commodity exchange and social labor.

Most contemporary conceptualizations of the public sphere are based on the ideas expressed in Jürgen Habermas' book The Structural Transformation of the Public Sphere – An Inquiry into a Category of Bourgeois Society, which is a translation of his Habilitationsschrift "Strukturwandel der Öffentlicheit:Untersuchungen zu einer Kategorie der bürgerlichen Gesellschaft". The German term Öffentlichkeit (Public Sphere) encompasses a variety of meanings and it implies a spatial concept, the social sites or arenas where meanings are articulated, distributed, and negotiated, as well as the collective body constituted by, and in this process, "the public". The work is still considered the foundation of contemporary public sphere theories, and most theorists cite it when discussing their own theories.