This paper reviews the current knowledge concerning treatment compliance in patients with end-stage renal disease (ESRD). Adult hemodialysis patient noncompliance with the treatment regimen is very common. Objective and subjective measures of compliance, however, are often weakly correlated. In addition, the patients may be compliant with some aspects of the treatment regimen, but noncompliant with others. Unfortunately, no current model of predicting the degree of hemodialysis patient compliance is very accurate. In spite of this, behavioral approaches to increase regimen compliance do have at least short-term efficacy. There is a paucity of published data on compliance in adult peritoneal dialysis patients and an almost complete absence of systematic studies of compliance in children and adolescent dialysis patients. A multidimensional nosology of compliance behavior in ESRD patients is, therefore, proposed, as well as an approach to the diagnosis of noncompliance in ESRD patients and to possible interventions.