The document defines special interest groups as private organizations that try to persuade elected officials to respond to the shared attitudes of its members. It notes that interest groups differ from political parties in that they do not nominate candidates for office but rather influence elections by representing specific interests. The document outlines both positives and negatives of interest groups, including that some have disproportionate influence due to funding and that some misrepresent their membership or use illegal tactics. It also provides examples of different types of interest groups and describes lobbying techniques used by interest groups to influence legislation.