There has been a recent uptick in several process‐oriented studies (e.g., Adrada‐Rafael, 2017; Leow, Thinglum, & Leow, 2022) that have employed concurrent data elicitation procedures (e.g., think aloud protocols) to explore how deeply L2 learners process, that is, depth of processing (DoP), L2 data. This chapter provides a succinct report of the origin of DoP, its theoretical and empirical presence in (I)SLA, and pedagogical implications for the instructed setting,