Voluntarism can be interpreted at the levels of values, structure, and ideology. In Western society, voluntarism rests heavily on secular and religious values originating in both Greco-Roman and Judeo-Christian traditions. Today the voluntary sector in the United States can be divided into five main types: social support networks, grassroots associations, nonprofit organizations, human service agencies, and private foundations. At the level of ideology, voluntarism can be interpreted as “civil society.”