This study examined the acquisition of L2 English vocabulary with clickers, focusing on the role of individual differences. Following a pretest-posttest design, we measured perception and performance among 61 English learners who took part in a vocabulary acquisition treatment, in which they answered Multiple Choice Questions (MCQs) via clickers (experimental group) or hand-raising (control group). Findings show that students have positive perceptions of clickers across all analytical measures adopted and that clickers promote vocabulary learning. However, the differences in learning gains between the two groups were not significant, indicating individual differences among learners. Four of the learners who exhibited 'extreme' (lowest/highest) perception and performance scores were selected for further analyses. The presence of individual differences in clicker-enhanced learning suggests the technology should be carefully implemented to accommodate learners' individual differences. [For the complete volume, "CALL and Professionalisation: Short Papers from EUROCALL 2021 (29th, Online, August 26-27, 2021)," see ED616972.]