In this article, we examine the mental processes and representations that are required of laypersons when learning about science issues from texts. We begin by defining scientific literacy as the ability to understand and critically evaluate scientific content in order to achieve one's goals. We then present 3 challenges of learning from science texts: the intrinsic complexity of science phenomena, the need to coordinate multiple documents of various types, and the rhetorical structure of the texts themselves. Because scientific information focuses on models, theories, explanations, and evidence, we focus on how explanatory and argumentative texts are processed. Then we examine 2 components of executive control in reading--goal-directed guidance and evaluation of content-that readers can acquire and adopt to deal with these challenges. Finally, we discuss 3 implications that these theories and empirical findings have for interventions intended to improve laypersons' understanding of scientific information.