How much a reader knows about a topic is one of the best predictors of comprehension. When readers engage with a text for which they have limited BK, the text is more difficult to understand. Even when the background is there, locating and retrieving it can be another matter. And then there’s the issue of assessment–how do you know what they know, and what they don’t know? We’ve been thinking, talking, and writing about background knowledge. Why do you think background knowledge gets neglected in comprehension instruction?