Uncovering Sampling Biases, Advancing Inclusivity, and Rethinking Theoretical Accounts in Second Language Acquisition: Introduction to the Special Issue SLA for All?

Abstract The social sciences have grappled with sampling biases, perhaps most notably the prevalent reliance on convenience samples drawn from university student populations. Researchers in second language acquisition (SLA) have likewise taken steps to assess and address the scope of these biases and their effects on theory construction. This special issue presents a collection of replications and registered replication reports comprising one such initiative, titled SLA for All? The replications aimed to evaluate the generalizability of findings from foundational SLA studies, which were obtained with university‐educated participants, to nonuniversity participant groups. In this introduction to the special issue, we review and discuss the general failure to replicate the initial results, the complex notion of replication, and questions of research ethics. We offer an in‐depth reflection on how our perspectives, practices, and future plans have evolved and conclude with a vision for a more inclusive, diverse, and informative approach to SLA research going forward.