From the 1950s to 1990s, parental monitoring was conceptualized and studied as an independent construct, driving changes in youth adjustment. In the past two decades, parental monitoring has instead come to be conceptualized in many papers as simply a way to acquire parental knowledge, with knowledge in turn driving changes in youth adjustment. We argue that this re-conceptualization is not yet supported by empirical evidence and is strongly contradicted by theory, because parental monitoring may impact youth adjustment in several plausible ways that do not involve acquiring knowledge. As a result, we recommend that the field decouple the study of parental monitoring and parental knowledge, and regard each as a construct of independent scientific interest for determining youth adjustment.