Depression is the most common psychopathological condition among patients with end-stage renal disease (ESRD), yet it is still under-recognized and misdiagnosed. Depression reduces quality of life and has a negative clinical impact upon sufferers with chronic illness, including ESRD. This article discusses the negative effects of depression among the ESRD population treated with dialysis, the prevalence of the condition, the methodological issues involved with screening and treatment, and the possible psychological and somatic causes. There is a need to identify the prevalence of the disorder by effective methods, overcome the current issues surrounding depression assessment and to undertake trials of suitable treatments.