In 2001, with support from National Science Foundation, the National Research Council began a review of the evidence concerning whether or not the National Science Education Standards have had an impact on the science education enterprise to date, and if so, what that impact has been. This publication represents the second phase of a three-phase effort by the National Research Council to answer that broad and very important question. Phase I began in 1999 and was completed in 2001, with publication of Investigating the Influence of Standards: A Framework for Research in Mathematics, Science, and Technology Education (National Research Council, 2002). That report provided organizing principles for the design, conduct, and interpretation of research regarding the influence of national standards. The Framework developed in Phase I was used to structure the current review of research that is reported here. Phase II began in mid-2001, involved a thorough search and review of the research literature on the influence of the NSES, and concludes with this publication, which summarizes the proceedings of a workshop conducted on May 10, 2002, in Washington, DC. Phase III will provide input, collected in 2002, from science educators, administrators at all levels, and other practitioners and policy makers regarding their views of the NSES, the ways and extent to which the NSES are influencing their work and the systems that support science education, and what next steps are needed.