orInverse relations, or "trade-off effects," are a common outcome of interlanguage development: a learner may increase performance in one linguistic domain while simultaneously decreasing performance in another. In this study, we investigate the relationships between one aspect of fluency (pause usage) and two aspects of syntactic complexity (utterance length and subordination) in relation to the location of pauses (between-clause or within-clause) in second-language (L2) oral narratives. The longitudinal analysis is based on monologic data produced by 16 English-speaking L2 learners of Spanish who participated in a seven-week study-abroad program in Spain. Overall, the learners decreased their silent-pause rate over the course of the program while concurrently increasing their number of syntactically complex clauses. Notably, the data suggest a systematic trade-off between pausing and complexity: the learners consistently produced more pauses (i.e. decr/eased fluency performance) during the elocution of the most complex clauses involving clausal subordination (i.e. increased complexity performance) in comparison to utterances lacking such subordination. We contextualize the findings within models of oral production and discuss how this research generates new insight into the processing factors that modulate pause usage in L2 speeclh.