Word-order rules impose major constraints on linguistic behavior. For example, adjectives appear before nouns in English, and after nouns in French. This means that constraints on word order must be language-specific properties upheld on-line by the language system. Despite the importance of these rules, little is known about how they operate. We report an influence of word order on the activation of phonological representations. Participants were presented with colored objects and asked to name either the colors or the objects; the phonological similarity between the object and color names was manipulated. French speakers showed a phonological congruency effect in color naming, but not in object naming. English participants yielded the opposite pattern: a phonological effect in object naming, but not in color naming. Differences in the typical order of nouns and adjectives in French and English provide a plausible account for this cross-linguistic contrast. More generally, these results provide direct evidence for the operation of word-order constraints during language production.