Dream speech is an understudied area of dream research worthy of attention for its potential to shed light on the nature of the interactions between the dream-self and dream-others, the patterns of discourse that occur among dream characters, and the structure and content of dream speech itself. The history of the study of dream speech is surveyed. Investigation of the structure and content of dream speech points to interesting similarities and differences in waking, imagined, and dreamed speech. Dream speech data support recent evidence that higher-order cognitive activity is a feature of dreaming no less than of waking thought. The study of dream speech offers a window on understanding dream structure and content more broadly.