The elderly are at high risk for acute kidney injury (AKI). With the aging of the population, the demand for intensive care unit (ICU) admission from older patients will continue to rise, and this clinical entity will likely become increasingly common. In this article we review the relevant literature, discuss the age-related changes that render older people prone to AKI development, and examine the most frequent etiologies for renal impairment in these patients. We also consider the difficulties in achieving an early diagnosis in the elderly ICU patient, the particularities related to AKI treatment in this age group, and the data available on differences in renal recovery and mortality between the young and the old with renal injury. More importantly, we highlight the methods for prevention of AKI development or worsening in the elderly critically ill patient.