Individuals who speak English as a second language vary in their ability to produce appropriate stress, which often impedes their intelligibility. The present study investigated the production of lexical stress by native speakers of English as well as learners of English. Minimal pairs were recorded by 8 native speakers of English and 8 Arabic learners of English. A second experiment examined use of acoustic cues to indicate stressed syllables in Arabic (8 speakers). In both experiments, four acoustic cues were examined: duration, fundamental frequency, amplitude, and second formant frequency. Differences in the use of these cues were observed across speaker groups (native and non-native speakers) for fundamental frequency and second formant frequency. These differences in use of cues to signal stress were only partially related to use of these acoustic cues in the speakers’ first language.