Acute kidney injury (AKI) is an increasingly common clinical problem with significant impact on long-term patient outcome. Recent clinical trials demonstrate that AKI is closely related to the progression of chronic kidney disease (CKD) and end-stage renal disease, though the precise mechanisms linking AKI to CKD remain unclear. While inflammation, microvascular rarefaction and hypoxia are involved in the AKI-to-CKD continuum, proximal tubule injury seems to play an important role in the progression of CKD. In this review, we focus on the mechanisms of the AKI-to-CKD continuum, especially the mechanism by which injury to the proximal tubules triggers progression to CKD. Elucidating the mechanisms involved in the AKI-to-CKD continuum will support the development of therapeutic options to prevent progression from AKI to CKD. © 2016 S. Karger AG, Basel.