Recently, there has been increasing interest in better understanding the transition from the pre−end-stage renal disease (ESRD) phase to the ESRD phase of chronic kidney disease (CKD), defined operationally as before and after initiation of long-term renal replacement therapy. For example, this transition is the focus of a new US Renal Data Systems (USRDS) Special Study, which published a chapter on “transition of care” in the 2015 USRDS Annual Data Report.1 During this transition, patients are at a very vulnerable state and rates of adverse events are very high.