This chapter aims to review current research on individual differences in multiple documents (MD) comprehension and to discuss the implications of these differences for educational research and practice. Models of MD comprehension describe how readers construct coherent mental representations based on documents that present diverse accounts regarding a particular issue. The chapter addresses several cognitive differences that have been found to play a role in MD comprehension: reading fluency, working memory, prior knowledge, prior beliefs, and strategic processing. An important component in text comprehension is readers' identification of semantic connections between different pieces of information in the text, and also between that information and readers' prior knowledge. Contemporary models of text comprehension all include prior knowledge as a critical factor in readers' construction of meaning from text. Epistemic criteria and standards enable evaluating the quality and reliability of one's own or others' knowledge representations.