Drawing on work from cognitive psychology, a vast body of research has examined the role of working memory (WM) in second-language (L2) development, processing, and use (e.g., Linck et al., 2014). Our ability to discern such relationships, however, may be obscured by the different measures of WM that are adopted and employed by L2 researchers. There exist a daunting number of WM tasks, and the variability in task design, implementation, and scoring adds to the challenge of accurately measuring WM capacity and interpreting findings. To this end, this chapter presents a methodological synthesis that surveyed the literature spanning 20 years (2001-2020) of WM-L2 research to describe the use of six common WM tasks. We coded a total of 329 unique samples on a range of features related to the WM tasks and reporting practices. Our findings suggest that, among the six most common WM tasks used in L2 research, task design and scoring procedures tend to diverge more than converge within and among the tasks. We also found neglected areas in reporting practices in the WM-L2 domain. Based on our findings, we provide insights into the use of the WM tasks and future directions to help researchers make informed decisions for measuring WM and interpreting findings critically.L38