In a Review, researchers provide a critical evaluation of research linking glymphatic dysfunction with Alzheimer’s disease. Since its discovery over a decade ago, the glymphatic system is the fluid exchange network that clears metabolic waste from the central nervous system, including harmful proteins like amyloid-beta (Aβ) and tau – and has been extensively studied in animal models and linked to various risk factors for Alzheimer’s disease (AD). However, in humans, the evidence remains largely correlative: while associations between glymphatic dysfunction and AD pathology have been observed, its causal role remains poorly understood. In this Review, Samantha Keil and colleagues provide an extensive overview of the current state of research with a focus on current approaches used to assess glymphatic function clinically. According to Keil et al., the main challenges in understanding glymphatic dysfunction’s role in human AD are due to anatomical and physiological differences between model species and humans, as well as limitations in imaging techniques used to measure glymphatic exchange in the human brain. To address this, the authors argue that the development of validated, noninvasive tools to measure glymphatic activity in humans should be a top priority in the field. Advances in neuroimaging, fluid biomarkers, and potentially wearable or device-based monitoring could enable longitudinal studies to determine whether impaired glymphatic function precedes AD pathology or cognitive decline. According to Keil et al., these advances would allow researchers to test whether enhancing glymphatic clearance – either pharmacologically, behaviorally, or technologically – could serve as a primary prevention strategy and represent a paradigm shift in AD therapeutics.