This article demonstrates how the Comparative Method can be applied to cross-linguistic research on language acquisition. The Comparative Method provides a systematic procedure for organizing and interpreting acquisition data from different languages. The Comparative Method controls for cross-linguistic differences at all levels of the grammar and is especially useful in drawing attention to variation in contexts of use across languages. This article uses the Comparative Method to analyze the acquisition of verb suffixes in two Mayan languages: K'iche' and Yucatec. Mayan status suffixes simultaneously mark distinctions in verb transitivity, verb class, mood, and clause position. Two-year-old children acquiring K'iche' and Yucatec Maya accurately produce the status suffixes on verbs, in marked distinction to the verbal prefixes for aspect and agreement. We find evidence that the contexts of use for the suffixes differentially promote the children's production of cognate status suffixes in K'iche' and Yucatec.