The authors summarize the current understanding of renal failure in children. They define hyperazotaemia, chronic renal insufficiency, acute and chronic renal failure and various stages of chronic renal failure according to the international guidelines. The most common causes of renal failure in childhood are indicated. Metabolic changes, based mainly on chronic renal failure, and the stratégy of possible conservative treatment as well as renal replacement therapy are analyzed. In addition to treatment using drugs, dietary and non-medical treatment is discussed. Finally, the principles of particular renal replacement methods are explained, as are the indications and contraindications.

        Key words: acute and chronic renal failure, chronic renal insufficiency, management of chronic renal failure, renal replacement therapy.