Institutional reform tends to happen in response to changes in the political environment. The political landscape of the House was dramatically altered in the 1970s when progressive members pursued institutional reforms that would democratize the chamber in response to the public's demand for greater government accountability. In a 1965 examination of congressional responses to the twentieth century, Samuel P. Huntington argued that government institutions that are incapable of adjusting to social change, as well as to new viewpoints, needs, and political forces, will eventually face an adaptation crisis. The 1970s trend toward individualistic behavior in the House can be explained partially by the parallel expansion of social movements and the interest group community. The House reforms of the 1970s helped to create a political environment that fostered the growth of member-to-member giving. While campaign finance reforms regulated the raising and spending of funds, they also encouraged political action committee (PAC) formation.