The School-to-Work Opportunities Act of 1994 requires the Secretaries of Education and Labor to conduct an evaluation of school-to-work. The evaluation is to "track and assess the progress of implementation of State and local programs and their effectiveness." In implementing this provision, the Secretaries have commissioned a process evaluation which will track and assess implementation progress. However, assessing the effectiveness of school-to-work raises many challenging issues which cannot be addressed by a process evaluation. As background for the remainder of the volume, this introductory chapter first summarizes the intent and provisions of the School-to-Work Opportunities Act. It then summarizes the evaluation and other data collection activities related to school-to-work which are already underway. The final section offers conclusions about the gap in current evaluation activities -- the need for a net impact evaluation.