The National Opinion Research Center at the University of Illinois at Chicago had conducted almost annually since 1972 the General Social Survey (GSS) to uncover the trends of societal opinions and practices. In 1988 and again in 1998, the GSS included a religion module in addition to core religious items, with questions ranging from Bible reading and church attendance to charitable giving. In this module, the respondent was asked for the name and location of his congregation. Because the general sampling procedure used by the GSS was nationally representative, so the list of congregations generated by that sample was similarly representative; thereby this method produced the best congregational sample in existence at that time. <p>The National Congregations Study (NCS), conducted by University of Illinois at Chicago with Dr. Mark Chaves directing, used the sample of congregations generated by the GSS to study the characteristics congregational life on a national, not just local, level. The study investigated such aspects of church life as the ties to neighborhood and denominational structures, institutions created by congregations, social services provided directly by the church, worship practices, and features of growing and declining congregations. <p>The data collected by the GSS is available in various forms on the Internet at such sites as the <a href='http://www.icpsr.umich.edu/index-medium.html'>Inter-university Consortium for Political and Social Research</a> and <a href='http://sda.berkeley.edu:7502/D3/GSS2000/Doc/gss2.htm'>University of California, Berkeley's Survey Documentation and Analysis archive</a>. Dissemination and analysis of the information collected by the NCS is covered in Lilly Endowment #990005 entitled "Dissemination of National Congregations Study."