Acute kidney injury (AKI) is a serious and as yet incompletely understood disorder in which sudden impairment of kidney function occurs secondary to one or more of a variety of underlying conditions. This disorder is very common in (elderly) ICU patients and is associated with very high mortality. Many of those who survive suffer from permanent kidney failure and other long-term morbidities, which may include cardiovascular disease and immune dysfunction. Epidemiologic evidence suggests that AKI is not a single disease, but a syndrome comprised of multiple, often coexisting, etiologies. Being usually part of multiorgan failure syndrome, it calls for multiple organ support therapy. The publication at hand contains sections on prerenal azotemia syndromes, dying 'of' or 'with' AKI, pathophysiology of sepsis-induced acute kidney injury, developments in prevention / treatment / rehabilitation, and renal support. Reporting the latest recommendations from experts, it provides valuable information for those that are interested in understanding the disorder and its treatment options.