The distribution of grammatical units (GUs) across intonation units (IUs) is analyzed in a corpus of 2,072 intonation units of Wardaman monologic oral narrative, and compared to a previously published study of English and several other languages. Since English and Wardaman are structurally very different languages, any common patterns in the mapping of grammatical units to intonation units would be of considerable interest as potential grammar-discourse universals. The Full GU Condition—IUs are almost always full GUs—holds in Wardaman as well as English and other languages. Both English and Wardaman employ a substantial number of grammatically independent noun phrase intonation units. Three factors constrain the occurrence of GUs in a single IU in English, in descending order of strength: parallelism, complexity and distance. All three factors also hold in Wardaman in the same order of strength. The behaviour of the IU-GU mapping in Wardaman supports critiques of the analyses of arguments as adjuncts and of modifiers as appositive phrases. On the other hand, spoken English displays more grammatical characteristics similar to Wardaman than prescriptive written English.