We review research by us and others on the development of auditory-visual speech perception in order to draw out issues of interest, pinpoint unanswered questions, and highlight future research directions. Studies using the McGurk Effect have shown that Japanese adults use visual speech information less than do English language adults. Infants perceive the McGurk Effect, and for English language children, it appears that auditory-visual speech perception improves over age, especially between 6 and 8 years. However, the same is not the case for Japanese children.