This article reviews current policy trends concerning the practice of ability grouping in K–12 science education. Relevant statements of key policy-making, policy-influencing organizations such as the NSTA, AAAS, NSF, the National Research Council, the U.S. Office of Education Department of Civil Rights, NAACP, the National Governors' Association, programs related to the Jacob Javits Grants for the Gifted and Talented, and others are summarized. The author's interpretation of the various positions are presented herein. The article also explores the research base supporting the various policies on grouping by examining selected general research literature on grouping, followed by research that is science education specific. Methodological issues color the research findings. The ethical and pragmatic implications of developing research and policy are discussed. The conclusions are that there is a dearth of recent empirical research specifically related to ability grouping in science, and that the time is ripe for the concerted development of a research agenda by key players in science education reform. Moreover, as controversial and value-laden as the topic is, it should be noted that grouping practices alone are unlikely to influence science education reform unless considered in the context of comprehensive restructuring efforts at the local school level.