<i>Background/Aims:</i> Long-term outcome after critical illness is important. After acute kidney injury (AKI) one measurement of such long-term outcome is assessment of renal recovery. <i>Methods:</i> A literature search was performed using the Medline database from 1960 to the present. The attempt was to include major clinical trials and other systematic reviews published in the field of renal recovery after critical illness. <i>Results:</i> More than 15 studies have covered the topic of renal outcome after intensive care, but the results are ambiguous. Studies from the mid-1990s showed that AKI survivors were at great risk of becoming dialysis dependent for life, with non-recovery reported at around 30%. Later investigations found lower risks, with non-recovery between 5 and 8% depending on the choice of continuous or intermittent renal replacement therapies. <i>Conclusion:</i> Continuous renal replacement therapies may be associated with better chances of renal recovery. Determining when and how to measure long-term renal outcome remains a matter of controversy.