As the number of candidates who repeat English language proficiency tests more than once to meet a certain cutscore (e.g., for university admission) or to demonstrate progress (e.g., after instruction) continues to increase dramatically, there is a need for more research on the attributes and test performance of test repeaters. This article provides an initial discussion of some of the key validity issues that can arise when interpreting and using repeaters' scores on second-language (L2) proficiency tests and some of the methodological considerations and challenges when examining repeaters' test performance. A key validity question is whether changes in repeaters' test scores across test occasions are due mainly to changes in the construct of interest. Another question is whether construct-irrelevant factors contribute significantly to variability in test scores across test occasions. The article concludes with a call for more research on the attributes and performance of repeaters of L2 proficiency tests to inform the validity arguments of these tests, test score users, and test validation and L2 acquisition research in general.