This document discusses interest groups and their role in influencing government. It defines interest groups as collections of people who share common interests and seek to influence policy. Interest groups engage in tactics like lobbying to achieve their goals. Examples are given of different types of interest groups, such as single-issue groups, as well as tactics they use like litigation. Problems that can arise with interest groups are also outlined, such as the disproportionate influence of some groups. Key terms related to interest groups and their activities are defined.