Plausibility judgments rarely have been addressed empirically in conceptual change research. Recent research, however, suggests that these judgments may be pivotal to conceptual change about certain topics where a gap exists between what scientists and laypersons find plausible. Based on a philosophical and empirical foundation, this article presents a theoretical model of the role of plausibility judgments in conceptual change (PJCC) with implications for epistemic cognition. The PJCC moves beyond the limitations of cold cognitive processing by incorporating the warmer constructs of affect, motivation, and motivated reasoning. We review recent research in plausibility judgments that informed the PJCC's development and discuss components of the model. Of particular note is the importance of using explicit critical evaluation to reappraise plausibility judgments that may have been originally made through implicit cognitive processes. We also suggest potentially productive areas of future research based on the PJCC model.