Dialysis patients account for 1%-9% of all intensive care unit (ICU) admissions. As a result of the increasing prevalence of patients treated with long-term dialysis and the changing demographics of this population, the number of dialysis patients requiring hospitalization and ICU support is expected to increase. Critically ill dialysis patients have more comorbid conditions and higher severity of illness than the general population, resulting in higher ICU and in-hospital mortality rates, but lower than for critically ill patients with acute kidney injury, suggesting that illness severity may contribute more to adverse outcomes than dialysis status. This review focuses on the epidemiology, prognosis, and short- and long-term outcomes of long-term dialysis patients admitted to the ICU, with data suggesting that dialysis patients have reasonable outcomes after ICU admission compared with the general population. It is important to recognize that illness severity and comorbid conditions rather than dialysis status account for much of the observed differences in short-term mortality rates. There are limited data to guide decision making regarding which dialysis patients may benefit from ICU admission, with common prognostic scoring systems routinely overestimating mortality in dialysis patients.