Several high-level committees have concluded that current domestic and global trends are threatening America's global science and engineering (S&E) preeminence. Of the challenges discussed, few are thought to be as serious as the purported decline in the supply of high quality students from the beginning to the end of the S&E pipeline--a decline brought about by declining emphasis on math and science education, coupled with a supposed declining interest among domestic students in S&E careers. However, our review of the data fails to find support for those presumptions. Rather, the available data indicate increases in the absolute numbers of secondary school graduates and increases in their math and science performance levels. Domestic and international trends suggest that that U.S. schools show steady improvement in math and science, the U.S. is not at any particular disadvantage compared with most nations, and the supply of S&E-qualified graduates is large and ranks among the best internationally. Further, the number of undergraduates completing S&E studies has grown, and the number of S&E graduates remains high by historical standards. Why, then, is there a purported failure to meet the demand for S&E college students and S&E workers? Analysis of the flow of students up through the S&E pipeline, when it reaches the labor market, suggests the education system produces qualified graduates far in excess of demand: S&E occupations make up only about one-twentieth of all workers, and each year there are more than three times as many S&E four-year college graduates as S&E job openings. So it is not clear, even if there were deficiencies in students' average S&E performance, that such deficiencies would necessarily be insufficient to meet the requisite S&E demand. While improving average math and science education at the K-12 level may be warranted for other reasons, such a strategy may not be the most efficient means of supplying the S&E workforce. Workforce development and education policy requires a more thorough analysis than appears to be guiding current policy reports. The available evidence points, first, to a need for targeted education policy, to focus on the populations in the lower portion of the performance distribution. Second, the seemingly more-than-adequate supply of qualified college graduates suggests a need for better understanding why the "demand side" fails to induce more graduates into the S&E workforce. Third, public and private investment should be balanced between domestic development of S&E workforce supply and global collaboration as a longer-term goal. Policy approaches to human capital development and employment from prior eras do not address the current workforce or economic policy needs. (Contains 26 footnotes, 5 figures, and 3 tables.) [An earlier version of this paper was presented at the meetings of the Association for Public Policy Analysis and Management, October 2006.]