This document reports on the findings of an NSF-funded conference (STEM ACT) on the alternative certification of science teachers. The conference explored the issues that have arisen in science education as a result of the proliferation of alternative certification programs in the United States, and to identify the research that needs to be done to reconcile the rapid growth of these programs with the demands that national standards and state curriculum frameworks put on science teacher quality. Alternative certification for science teachers has become a tapestry woven of various strands - political and professional, ideological and academic. Given the complexity of issues, the continued growth, and the on-going investment of public resources associated with alternative certification, a comprehensive, in-depth and systematic descriptive analysis is needed to help evaluate the ways in which alternative teacher certification does or does not address teacher supply and demand, and science teacher quality. Therefore, one purpose of the STEM ACT conference was to identify key features and issues relating to alternative teacher certification as the basis for suggesting a more systematic approach to the study of alternative teacher certification efforts. The STEM ACT conference was held in early May 2006 in Arlington, VA. It was a working conference in which 65 participants presented and discussed 42 papers. Most of the papers are available on-line on the conference website. The conference was organized along three themes: (1) An overview of the existing policy on alternative certification of secondary (middle and high school) science teachers in the US, including key assumptions and questions; (2) A synthesis of existing research about the needs, methods, and outcomes of alternative certification for science teachers; and (3) An in-depth look at existing practice through the examination of particular cases of alternative programs for science teacher preparation. On the last day of the conference participants were grouped into writing committees to begin the preparation of white papers on each theme. The findings of the conference are presented in this document. Appendixes list papers presented. (Individual sections contain references, tables, and figures.)