The execution of the Selective Service Act in 1917 proved extremely successful in mobilizing both manpower and public opinion in support of America's war aims, but is selective service still relevant to the United States military in the 21st century? This paper will examine the Selective Service Act of 1917 and consider its antecedents, execution, and influence on the United States military today. Research was conducted by means of a literature review of historical documents and current articles relevant to the issue. Two goals of this research are to explore the success of the original Selective Service Act from its historical perspective and to consider aspects which may be relevant today. The position taken is that although the U.S. military and the nation as a whole have changed in significant ways, selective service continues to serve America as a safeguard against threats to national security.