Advocacy groups (also known as
pressure groups,
lobby groups,
campaign groups,
interest groups, or
special interest groups) use various forms of
advocacy in order to influence
public opinion and/or policy. They have played and continue to play an important part in the development of political and social systems. Groups vary considerably in size, influence, and motive; some have wide ranging long term social purposes, while others are focused on and are a response to an immediate issue or concern.