Few would argue that one person could not make a difference in American politics. But there is power in numbers, and political institutions are more likely to respond to a collective rather than to an individual voice. An interest group is an organization whose members share common concerns and try to influence government policies affecting those concerns. Interest groups are also known as lobbies. Lobbying is one of the ways interest groups shape legislation and bring the views of their constituents to the attention of decision-makers.

Lobbying efforts are directed primarily at the national level: committees of Congress that consider legislation, administrative agencies that are responsible for writing or enforcing regulations, and executive departments. Lobbyists depend on their personal relationships with members of Congress and the executive branch, which are based on keeping in regular contact. Many lobbyists have served in government themselves. This means they have worked, in some cases for years, with the very people they are now lobbying, and this experience gives them invaluable insights into how things are accomplished in Washington.

The critical legislative work in Congress takes place in committees. Lobbyists testify at committee hearings, provide the staff with information, and, more frequently than most people realize, actually write the legislation. They are sophisticated professionals and do not simply say to senators, "Vote for this bill or else," but instead explain why the bill is important to their constituency as well as what impact it will have in the senator's state. A lobbyist may have a politically connected member of the interest group contact the senator.

Elected officials as well as the public are often critical of the roles of "special interests" in the political process. The activities of lobbyists can smack of vote-buying and influence-peddling. There are so many organized lobbies today, representing numerous segments of society and addressing such a wide range of issue, that the distinction between "special interests" and those of the American people may no longer be valid. In a sense, interest groups are us.