The Structural Transformation of the Public Sphere is Jürgen Habermas's examination of a type of publicity that originated in the 18th century, but still has modern relevance. It begins by attempting to demarcate what Habermas calls the bourgeois public sphere. He defines the public sphere as the sphere of private people who join together to form a "public." He traces the history of the division between public and private in language and philosophy.

Prior to the bourgeois public sphere there existed what Habermas calls representative publicity, which existed from the Middle Ages until the 18th century. It involved the king or lord representing himself before an audience. In this system, the king was the only public person, and all others were spectators. The public and private realms were not separated.

Economic developments were vital in the evolution of the public sphere. Habermas emphasizes the role of capitalist modes of production, and of the long-distance trade in news and commodities in this evolution. The most important feature of the public sphere as it existed in the 18th century was the public use of reason in rational-critical debate. This checked domination by the state and the illegitimate use of power. Rational-critical debate occurred within the bourgeois reading public, in response to literature, and in institutions such as salons and coffee-houses. Habermas sees the public sphere as developing out of the private institution of the family, and from what he calls the literary public sphere, where discussion of art and literature became possible for the first time. The public sphere was by definition inclusive, but entry depended on one's education and qualification as a property owner. Habermas emphasizes the role of the public sphere as a way for civil society to articulate its interests.

The development of the fully political public sphere occurred first in Britain in the 18th century. The public sphere became institutionalized within the European bourgeois constitutional states of the 19th century, where public consensus was enshrined as a way of checking domination. The fully developed public sphere was therefore dependent on many social conditions, which eventually shifted.

Habermas argues that the self-intepretation of the public sphere took shape in the concept of "public opinion," which he considers in the light of the work of Kant, Marx, Hegel, Mill and Tocqueville. The bourgeois public sphere eventually eroded because of economic and structural changes. The boundaries between state and society blurred, leading to what Habermas calls the refeudalization of society. State and society became involved in each other's spheres; the private sphere collapsed into itself.As part of this shift, the key feature of the public sphere—rational-critical debate—was replaced by leisure, and private people no longer existed as a public of property owners.

Habermas argues that the world of the mass media is cheap and powerful. He says that it attempts to manipulate and create a public where none exists, and to manufacture consensus. This is particularly evident in modern politics, with the rise of new disciplines such as advertising and public relations. These, and large non-governmental organizations, replace the old institutions of the public sphere. The public sphere takes on a feudal aspect again, as politicians and organizations represent themselves before the voters. Public opinion is now manipulative, and—more rarely—still critical. We still need a strong public sphere to check domination by the state and non-governmental organizations. Habermas holds out some hope that power and domination may not be permanent features.