Why is it easy for some people to learn to read, and difficult for others? It’s a tough question with a long history. We know that it’s not just about raw intelligence, nor is it wholly about repetition and dogged persistence. We also know that there are some conditions that, effort aside, can hold a child back. Socioeconomic status, for instance, has been reliably linked to reading achievement. And, regardless of background, children with lower general verbal ability and those who have difficulty with phonetic processing seem to struggle.