Studies of the effectiveness of abstinence programs have yielded differing conclusions. A 2004 study by the Heritage Foundation (a self-described "conservative think-tank")<ref>[http://www.heritage.org/about/ The Heritage Foundation: Our Mission] "Founded in 1973, The Heritage Foundation is a research and educational institute - a think tank - whose mission is to formulate and promote conservative public policies based on the principles of free enterprise, limited government, individual freedom, traditional American values, and a strong national defense."</ref> found that virginity pledges significantly reduce premarital sex without putting backsliders at risk.<ref> Teens Who Make Virginity Pledges Have Substantially Improved Life Outcomes | Studies of the effectiveness of abstinence programs have yielded differing conclusions. A 2004 study by the Heritage Foundation (a self-described "conservative think-tank")<ref>[http://www.heritage.org/about/ The Heritage Foundation: Our Mission] "Founded in 1973, The Heritage Foundation is a research and educational institute - a think tank - whose mission is to formulate and promote conservative public policies based on the principles of free enterprise, limited government, individual freedom, traditional American values, and a strong national defense."</ref> found that virginity pledges significantly reduce premarital sex without putting backsliders at risk.<ref> Teens Who Make Virginity Pledges Have Substantially Improved Life Outcomes |