This study looks at the role of lexical stress in Urdu prosody. The literature on lexical stress is divided, with some authors developing algorithms for stress assignment, while others deny its relevance for prosody. We performed three experiments to investigate this issue. We found evidence that a strong increase in the duration of a syllable indicates stress and that lexical stress and phrasal intonation interact in a non-trivial manner. We also found that stress perception varies according to syllable weight with weight clash being a determining factor.