This paper presents an overview of the activation of background knowledge during text comprehension. We first review the cognitive processes involved in the activation of inferences during text comprehension, stressing the interaction between text and reader in the construction of situation models. Second, we review evidence for embodied theories of cognition and discuss how this new framework can inform our understanding of the nature and role of background knowledge. We then review the neuropsychological data on the activation of background knowledge during text comprehension. Finally, the paper presents existing and future challenges in researching the role of background knowledge both at a conceptual and a methodological level.