AbstractThe purpose of this investigation was to explore possible relationships between Socioscientific Issues instruction and students' development of reflective judgment. The usefulness of the Reflective Judgment Model as a tool for assessing the value of SSI is established in the parallels that can be drawn between them. Both involve ill‐structured problems requiring evidence‐based reasoning subject to differing interpretations by students, and both require examination, analysis and the blending of scientific and normative evidence, as students use that evidence to support a reasoned position. Results demonstrated both qualitative evidence revealing more sophisticated and nuanced epistemological stances toward higher stages of reflective judgment, as well as statistically significant gains within treatment groups with a moderately large effect size. Theoretical implications for advancing students' epistemological beliefs about evidence‐based argumentation and pedagogical implications for rethinking how to connect science with topics that are fundamentally meaningful to students are discussed. © 2008 Wiley Periodicals, Inc. J Res Sci Teach 46: 74–101, 2009