A special interest is a person, group, or organization attempting to influence legislators or other public officials in favor of one particular interest or issue. Examples might include a corporation lobbying to win a specific government contract; a trade association representing the interests of an entire industry seeking favorable tax policies or government regulations; or groups representing various sectors of society, such as labor unions, senior citizens or persons with disabilities.
Many scholars dislike the term "special interest", since it carries a loaded, negative connotation. In the academic literature, it has been replaced by the term "interest group". There is a lively debate amongst political scientists as to what exactly constitutes an interest group. Some hold that only groups with members (for instance, Common Cause or the NRA) are interest groups. Others feel that interest groups are any non-government groups that try to affect policy. Some people define it even more broadly, to include individual corporations, or even government agencies. Sometimes "interest groups" are used to refer to groups within society (e.g. seniors, the poor, etc.) who are not necessarily part of an organized group.