The decision to provide dialytic support and choosing the ideal moment to initiate therapy are common impasses for physicians treating patients with acute kidney injury (AKI). Although renal replacement therapy (RRT) has been extensively used in clinical practice for more than 30 years, there is a paucity of evidence to guide clinicians on the optimal utilization of RRT in AKI. In the absence of traditional or urgent indications, there is no consensus on whether dialysis should be offered and when it should be started. The lack of agreed-upon parameters to guide the decision, the fear of the risk of the procedure, and the possible contribution to worse prognosis with RRT have resulted in a considerable variation in practice among physicians and centers. In this review, we summarize the evidence evaluating time of initiation of RRT and discuss possible approaches for future trials in addressing this issue.