Deliberative democracy or discursive democracy is a form of democracy in which deliberation is central to decision-making. Deliberative democracy seeks quality over quantity by limiting decision-makers to a smaller but more representative sample of the population that is given the time and resources to focus on one issue.
 It often adopts elements of both consensus decision-making and majority rule. Deliberative democracy differs from traditional democratic theory in that authentic deliberation, not mere voting, is the primary source of legitimacy for the law. Deliberative democracy is related to consultative democracy, in which public consultation with citizens is central to democratic processes. The distance between deliberative democracy and concepts like representative democracy or direct democracy is debated. While some practitioners and theorists use deliberative democracy to describe elected bodies whose members propose and enact legislation, Hélène Landemore and others increasingly use deliberative democracy to refer to decision-making by randomly-selected lay citizens with equal power.
 Deliberative democracy has a long history of practice and theory traced back to ancient times, with an increase in academic attention in the 1990s, and growing implementations since 2010.  Joseph M. Bessette has been credited with coining the term in his 1980 work Deliberative Democracy: The Majority Principle in Republican Government.
 Deliberative democracy holds that, for a democratic decision to be legitimate, it must be preceded by authentic deliberation, not merely the aggregation of preferences that occurs in voting. Authentic deliberation is deliberation among decision-makers that is free from distortions of unequal political power, such as power a decision-maker obtains through economic wealth or the support of interest groups.
 The roots of deliberative democracy can be traced back to Aristotle and his notion of politics; however, the German philosopher Jürgen Habermas' work on communicative rationality and the public sphere is often identified as a major work in this area.
 Deliberative democracy can be practiced by decision-makers in both representative democracies and direct democracies. In elitist deliberative democracy, principles of deliberative democracy apply to elite societal decision-making bodies, such as legislatures and courts; in populist deliberative democracy, principles of deliberative democracy apply to groups of lay citizens who are empowered to make decisions. One purpose of populist deliberative democracy can be to use deliberation among a group of lay citizens to distill a more authentic public opinion about societal issues for other decision-makers to consider; devices such as the deliberative opinion poll have been designed to achieve this goal. Another purpose of populist deliberative democracy can, like direct democracy, result directly in binding law. If political decisions are made by deliberation but not by the people themselves or their elected representatives, then there is no democratic element; this deliberative process is called elite deliberation.
 James Fearon and Portia Pedro believe deliberative processes most often generate ideal conditions of impartiality, rationality and knowledge of the relevant facts, resulting in more morally correct outcomes. Former diplomat Carne Ross contends that the processes more civil, collaborative, and evidence-based than the debates in traditional town hall meetings or in internet forums if citizens know their debates will impact society.  Some fear the influence of a skilled orator.
 James Fishkin, who has designed practical implementations of deliberative democracy through deliberative polling for over 15 years in various countries, describes five characteristics essential for legitimate deliberation:
 Studies by James Fishkin and others have concluded that deliberative democracy tends to produce outcomes which are superior to those in other forms of democracy. Desirable outcomes in their research include less partisanship and more sympathy with opposing views; more respect for evidence-based reasoning rather than opinion; a greater commitment to the decisions taken by those involved; and a greater chance for widely shared consensus to emerge, thus promoting social cohesion between people from different backgrounds. Fishkin cites extensive empirical support for the increase in public spiritedness that is often caused by participation in deliberation, and says theoretical support can be traced back to foundational democratic thinkers such as John Stuart Mill and Alexis de Tocqueville. 
 Joshua Cohen, a student of John Rawls, argued that the five main features of deliberative democracy include:
 Cohen presents deliberative democracy as more than a theory of legitimacy, and forms a body of substantive rights around it based on achieving "ideal deliberation":
 In Democracy and Liberty, an essay published in 1998, Cohen updated his idea of pluralism to "reasonable pluralism" – the acceptance of different, incompatible worldviews and the importance of good faith deliberative efforts to ensure that as far as possible the holders of these views can live together on terms acceptable to all.
 Amy Gutmann and Dennis F. Thompson's definition captures the elements that are found in most conceptions of deliberative democracy. They define it as "a form of government in which free and equal citizens and their representatives justify decisions in a process in which they give one another reasons that are mutually acceptable and generally accessible, with the aim of reaching decisions that are binding on all at present but open to challenge in the future".
 They state that deliberative democracy has four requirements, which refer to the kind of reasons that citizens and their representatives are expected to give to one another:
 For Bächtiger, Dryzek, Mansbridge and Warren, the ideal standards of "good deliberation" which deliberative democracy should strive towards have changed:
 Consensus-based decision making similar to deliberative democracy has been found in different degrees and variations throughout the world going back millennia. The most discussed early example of deliberative democracy arose in Greece as Athenian democracy during the sixth century BC. Athenian democracy was both deliberative and largely direct: some decisions were made by representatives but most were made by "the people" directly. Athenian democracy came to an end in 322 BC. Even some 18th century leaders advocating for representative democracy mention the importance of deliberation among elected representatives.
 The deliberative element of democracy was not widely studied by academics until the late 20th century. According to Professor Stephen Tierney, perhaps the earliest notable example of academic interest in the deliberative aspects of democracy occurred in John Rawls 1971 work A Theory of Justice. Joseph M. Bessette has been credited with coining the term "deliberative democracy" in his 1980 work Deliberative Democracy: The Majority Principle in Republican Government, and went on to elaborate and defend the notion in "The Mild Voice of Reason" (1994). In the 1990s, deliberative democracy began to attract substantial attention from political scientists. According to Professor John Dryzek, early work on deliberative democracy was part of efforts to develop a theory of democratic legitimacy. Theorists such as Carne Ross advocate deliberative democracy as a complete alternative to representative democracy. The more common view, held by contributors such as James Fishkin, is that direct deliberative democracy can be complementary to traditional representative democracy. Others contributing to the notion of deliberative democracy include Carlos Nino, Jon Elster, Roberto Gargarella, John Gastil, Jürgen Habermas, David Held, Joshua Cohen, Amy Gutmann, Noëlle McAfee, Rense Bos, Jane Mansbridge, Jose Luis Marti, Dennis Thompson, Benny Hjern, Hal Koch, Seyla Benhabib, Ethan Leib, Charles Sabel, Jeffrey K. Tulis, David Estlund, Mariah Zeisberg, Jeffrey L. McNairn, Iris Marion Young, Robert B. Talisse, and Hélène Landemore.[citation needed]
 Although political theorists took the lead in the study of deliberative democracy, political scientists have in recent years begun to investigate its processes. One of the main challenges currently is to discover more about the actual conditions under which the ideals of deliberative democracy are more or less likely to be realized.
 Drawing on the work of Hannah Arendt, Shmuel Lederman laments the fact that "deliberation and agonism have become almost two different schools of thought" that are discussed as "mutually exclusive conceptions of politics" as seen in the works of Chantal Mouffe, Ernesto Laclau, and William E. Connolly. Giuseppe Ballacci argues that agonism and deliberation are not only compatible but mutually dependent: "a properly understood agonism requires the use of deliberative skills but also that even a strongly deliberative politics could not be completely exempt from some of the consequences of agonism".
 Most recently, scholarship has focused on the emergence of a 'systemic approach' to the study of deliberation. This suggests that the deliberative capacity of a democratic system needs to be understood through the interconnection of the variety of sites of deliberation which exist, rather than any single setting. Some studies have conducted experiments to examine how deliberative democracy addresses the problems of sustainability and underrepresentation of future generations. Although not always the case, participation in deliberation has been found to shift participants opinions in favour of environmental positions.
 The OECD documented nearly 300 examples (1986-2019) and finds their use increasing since 2010. For example, a representative sample of 4000 lay citizens used a 'Citizens' congress' to coalesce around a plan on how to rebuild New Orleans after Hurricane Katrina.