This study compares what we term information density in spoken versus written discourse by distinguishing between 2 broad classes of material in narrative texts: narrative information as conveyed through three types of propositional content-events, descriptions, and interpretations (Berman, 1997)-and ancillary information as conveyed by nonnovel, nonreferential, or nornarrative material. One hundred sixty texts were analyzed across the variables of modality (writing, speech), development (4th-, 7th-, and 11th-grade students compared with adults), and language (English, Hebrew). Calculation of information density revealed no significant differences between languages, indicating that the analysis has general applicability. Increase in narrative information proved to be a function of modality rather than age, because, across the population, spoken texts contained far more ancillary material than written. By contrast, the nature of narrative content changed as a function of development, with interpretive material increasing with age. The study thus underscores 2 key features of narrative text construction: Modality has a distinct effect on information density, and, with age, the core of narrative information (events and descriptions) becomes fleshed out by interpretive and story-external elements.