The purpose of the following study was to investigate what Swain has labeled “comprehensible output” (Swain 1985). Negotiated interactions between a native English speaker (NS) and ten nonnative speakers (NNSs) of English were examined to find out how the nonnative speakers made their interlanguage utterances comprehensible when the native speaker indicated difficulty in understanding them. On the basis of theoretical work Hatch, 1978, Hatch et al., 1986; Schachter, 1986; Swain, 1985 and anecdotal evidence from NS-NNS interaction, it was believed that the NNSs would respond to the NS by modifying interlanguage morphosyntax, phonology, and lexicon and, in so doing, would employ more target- like use of English. Results of the study offered somewhat limited confirmation of these beliefs. The data revealed that the NNSs were, indeed, capable of modifying their interlanguage in response to the NS's requests for comprehensible output. However, such NNS modifications were relatively infrequent and virtually unnecessary because, typically, when signaling requests for clarification from the NNSs, the NS also modeled target, (modified) versions of NNS interlanguage utterances for them.