In ancient Greece, democracy (" by the common people") involved decision-making on policy and legislation by citizens in a popular assembly. For centuries thereafter, it was assumed that democracy was only possible in small, self-governing communes and towns, and was practised comparatively rarely. A different type of legislative body developed in the modern period to limit the power of rulers and hold them to account. This was the representative assembly or parliament, which acts on behalf of the people and is subject to election by them, or at least some of them. The idea of representation made possible the involvement of citizens in public affairs across the large territory of a modern state. Elections were eventually extended to the selection of the head of government (president or prime minister) as well as the national parliament or legislature. But who constitutes "the people"? From the dawn of democracy, the rights of citizenship were highly restricted, excluding women, slaves and foreign residents. In modern times, the right to vote was similarly restricted, for example, to male property owners. It took centuries of popular struggle to have this basic right extended to all adult men and women. It was only then that we could call a representative system fully democratic, embodying the two principles of popular control of government and equality among citizens in their right to political participation.

Elections constitute the basic democratic method for selecting those who make decisions on our behalf, and holding them accountable for their decisions. For elections to genuinely reflect the people's will, votes have to count equally, candidates for office have to be able to campaign freely, and there has to be a "level playing field" for governing and opposition parties and candidates in the electoral contest. Most infringements of these principles occur when governing parties or leaders refuse to accept the possibility that they might lose office, and try to prevent that from happening. However, holding elections does not make a democracy. People have to be able to influence their representatives on a continuous basis, and to communicate and organize with others on matters of common interest, independently of government. This requires an underpinning of guaranteed individual rights and freedoms, particularly of expression, association and assembly. These, in turn, require an independent judiciary to uphold them. Also crucial is the existence of free media of communication (press, broadcasting, the Internet) to ensure that there is independent information about the actions of public officials, and to facilitate communication and organization among citizens in defence and promotion of their interests. Basic economic and social rights – a minimum livelihood, health care and education – are also essential to democracy, since without these the right to participate in public affairs cannot be exercised effectively. It is for this reason that democracy and human rights can be seen as closely connected. Both have as their basic premise the equal worth of each individual, regardless of race, gender, personal belief or style of life.

Compared with authoritarian regimes, whether they be based on a controlling military, a single party, a ruling family, a personalized dictatorship, or some combination of these, democracies can claim significant advantages for their citizens: Ensuring basic freedoms. In a democracy, people are able to think, say and do what they wish within the law and with respect for others, to practise their beliefs and to live the kinds of life they choose. Free societies have always facilitated artistic innovation, scientific enquiry and philosophical speculation. Meeting popular needs. The more influence ordinary people have over government policy through democratic channels, the more likely government will reflect their concerns and aspirations, and meet their basic needs. Treating people equally. This basic democratic principle demands that government attends to people's interests equally in its policy and administration, without favour or discrimination. Although the practice may fall short of this standard, it is always open to improvement through campaigning by and on behalf of disadvantaged groups. Solving disagreement or conflict through debate, persuasion and compromise. The democratic emphasis on open debate assumes not only that there are differences of opinion and interest on most questions of policy, but that such differences have a right to be expressed and listened to. When such diversity finds expression, both open conflict and the resolution of differences is achieved through discussion, persuasion and compromise, rather than by the simple assertion of power. Enabling societal renewal. By providing for the routine and peaceful removal of politicians and policies that have failed or outlived their usefulness, democracies are able to ensure societal and generational renewal without the massive upheaval or disruption that attends the removal of key personnel in non-democratic regimes.

A popularly elected parliament or legislature plays a key democratic role in the separation of powers between itself and the government. It must approve all legislation and taxation, and is responsible for ensuring that all proposals before it are thoroughly tested and debated before becoming law. With its oversight powers, it scrutinizes the work of government by questioning ministers, inspecting documents and cross-examining state personnel. In addition, parliaments are responsible for ensuring that the benefits of democracy, as outlined above, are realized in practice by protecting basic rights and freedoms, representing the needs of the people to government and in the legislative process, treating constituents with equal respect, and maintaining dialogue, especially in deeply divided societies. They can do so more effectively if their membership is representative of public opinion and the social diversity of the population, and if they are continuously open to the public through various channels. Most parliamentarians are conscientious and hard-working; but they face a substantial challenge in convincing the public that this is so, that their work is important, and that they are not a remote class of people enjoying unjustified privileges at the expense of the taxpayer. Most parliaments now have strict rules on the declaration of earnings, expenses and outside interests by members. They also employ the latest means of communication in informing the public about their work and in responding to the concerns of their electorates.

Surveys show that political parties are the least trusted of all public institutions in almost all countries. Yet if they were abolished, or simply disappeared, we would soon find it necessary to reinvent them. This is because, in a large society, people can exercise little influence as individuals; they must join with others to have their voices heard. Political parties bring together those who share similar views and interests to campaign for public office, political influence and public support. In doing so, they perform a number of essential democratic functions: For electorates, they help simplify the electoral choice by offering broad policy positions and programmes among which to choose. For the more politically committed, they provide an opportunity for involvement in public affairs, a means of political education and a channel for influencing public policy. For governments, they provide a reasonably stable following of political supporters to enable them to enact their programmes, once elected. For oppositions, they provide a source of alternative policies, and a consistent basis for holding the government to account. However, these democratic functions have corresponding disadvantages that may forfeit public support. "Toeing the party line" can stifle independence of views and honest debate. Opposition can be divisive, and lead to "opposition for opposition's sake." In addition, the escalating cost of elections can mean that wealthy individual and corporate sponsors of party campaigns exercise more influence over the policy and legislative process than voters do. This influence can only be reduced by strict limits on donations and electoral expenditure, enforced by an independent commission with legal powers.

Male domination of public life. For most of history, and in most countries, government has been a male preserve. This is still true, and it is rare for women to be represented in public office in proportion to their numbers in the population. This not only undermines the democratic principle of equality, it deprives public life of the full contribution that women could make to it. Corruption among office-holders. Corruption is usually defined as the abuse of public office for private gain. It contradicts the principle that office in a democracy is exercised on behalf of the people, not the office-holder and his or her family, friends or personal connections. When chronic, corruption undermines public trust in government and support for the democratic process itself. "Tyranny of the majority." Although decisions taken in accordance with a majority view are necessarily more democratic than decisions taken by a minority, they can become oppressive when they infringe upon the basic democratic rights of an unpopular individual or group, or when an ethnic, linguistic or religious minority is permanently excluded from any share in power. Executive control over parliament. It is the task of elected governments to provide leadership in the policy and legislative process. However, where parliaments lack effective independence from the government, whether through inadequate resources and expertise, or through tight ruling party control, they are unable to carry out their oversight function effectively, with consequences for the quality of policy and legislation as well as reduced public accountability of the government. Lack of media pluralism. The key requirement for the communication media in a democracy is pluralism: multiple sources of information and diversity of views and opinions. This diversity can be threatened from two directions: from government, through control over public media or more subtle forms of pressure and censorship, and from the private sector, when there is undue concentration of ownership of different forms of media. Public apathy. Loss of public interest in politics, of confidence in government and of belief in the value of the democratic process is a potential danger to the survival of democracy itself. It is usually symptomatic of something seriously wrong with the governmental process, and of a widespread sense that people are powerless to change or influence it.

Many of the problems outlined above have no easy solution; even when there appears to be one, there may be little incentive for those in power to implement it. Almost always, improvement comes through organized pressure from the public itself. There are many examples of good practice from elsewhere, showing that change is, indeed, possible. Democracy's capacity for self-correction makes it unique as a system of government. Increases in the number of women holding elective office typically comes when political parties feel obliged, either through public pressure or legal requirement, to change their procedures for candidate selection so that women have the same chance as men to win a parliamentary seat. This is only a start, however. Parliamentary facilities and procedures, and party promotion processes, have to be such as to facilitate full participation by women members. There is no simple solution to corruption once it has become endemic. Paying public servants a decent wage so that they do not have an incentive to abuse their office by taking bribes may help with one side of the problem. Improving the likelihood of exposure and enforcement of sanctions on defaulters may serve as a deterrent on the other side. Here the media and anti-corruption organizations of civil society can play a significant role. Majority oppression of vulnerable or unpopular individuals or groups can best be prevented by constitutional protection of fundamental rights and freedoms, backed by effective law enforcement. The permanent exclusion of minorities from any share in political power can be addressed through the electoral system, through quota provisions, through power-sharing arrangements, or through decentralization of government, according to the circumstances. For parliaments to be fully independent of the executive arm of government, they need control over their own staffing, procedures and organization of business, effective powers of investigation, and sufficient resources and expertise to be able to carry out their functions without relying on the government. Ensuring that the incentives and sanctions available to party leaderships do not render parliamentarians subservient to government is, however, much more difficult to legislate. Government control of, or interference in, publicly funded broadcasting can best be prevented by establishing an independent broadcasting authority with a politically inclusive or non-partisan membership. Concentrations of media ownership can be addressed through legally enforceable limits on ownership, including cross-media interests. There is little evidence that people anywhere have lost interest in the major issues that affect their lives; rather, many have lost confidence in the institutions of representative democracy to do much about those issues, and in their own ability to influence those institutions. Improved electoral choice, more effective and responsive government, and better political leadership are all needed. There is no one solution.

In the economic sense, "globalization" indicates a process of liberalization and intensification of cross-border market transactions, through which national economies and governments become much more vulnerable to decisions over trade, investment, financial flows and currency movements that are taken outside the country's borders. At a wider level, globalization points to the increasing interdependence of global society, so that decisions taken by people and governments in one place affect what happens elsewhere in respect of the environment, physical security, public health, migration flows, criminal activity, tax evasion, and so on. Because these processes are beyond the reach of national governments, the effectiveness of democracy is diminished. What is the advantage of popular control over government if governments themselves are unable to determine what matters for the wellbeing of their citizens? These challenges to democracy can only be met by strengthening the processes of regulation and collective decision-making at the international level, either through inter-governmental cooperation, or through regional and international institutions based on a fair system of national representation. Yet these seem too remote for people to have any influence over them. Parliaments can help to give people some measure of say in the international arena. They need to exercise more actively the powers entrusted to them. In fact, parliaments, in accordance with national laws, need to assume these powers so as to ensure oversight and more influence over their governments' policies in international affairs. This should supplemented by greater inter-parliamentary co-operation and greater interaction between parliaments and international institutions.

It has been argued that democracies are poorly equipped to deal with the current threats to human security – environmental degradation, civil war and terrorism. The first requires unpopular, long-term decisions that politicians focused on the next election are reluctant to take. The second exposes democracy's impotence in the face of chronic armed conflict. And the third can only be met by limiting the very rights and freedoms that make democracy distinctive. According to this argument, all these threats require the kinds of authoritarian solutions that non-democratic regimes can impose more easily. This argument is simplistic, and overlooks the very real advantages of democratic methods. In the face of environmental challenges, people can be brought to alter deep-seated attitudes and life-styles only through exposure to honest public debate and persuasion, supported by progressive, citizen-based initiatives. Civil wars can only be brought to an end by the democratic methods of dialogue and compromise, assisted by domestic and international mediators. And terrorism is best combated if it is treated as a law-enforcement issue rather than a military campaign, and if the necessary cooperation among all communities is maintained by protecting the rights of due process and essential liberties for all. In all these respects, democracies have strengths that more authoritarian systems lack.

Just because the institutions of democracy developed over centuries in the West, it does not mean that the idea of democracy is of exclusively Western origin. The principle that ordinary people should have a say in the decisions that affect their lives, and that rulers should be accountable to them, is one that has emerged at different times and places across the world. Democracy is now a universal aspiration, even if it is not realized everywhere in practice. However, democracy cannot simply be imported from abroad. Its establishment and preservation are dependent on popular struggles inside each country. The idea of imposing democracy on a country from outside by force – promoting a people's self-determination through a systematic violation of it—is particularly problematic. The final statement of the 2005 World Summit explicitly links the value of democracy with "due respect for sovereignty and the right of self-determination."