Citrate is the recommended anticoagulant to maintain filter patency during CRRT. It has advantages over other forms of anticoagulation, including longer circuit life, reduced risk of bleeding and regulation of acid-base balance. Potential risks are citrate accumulation, hypo-and hypercalcaemia, hypernatraemia and hypomagnesaemia. Mitochondrial failure and severe liver failure are contraindications to regional citrate anticoagulation. Close monitoring of pH, ionized calcium and electrolytes is needed to avoid complications. In this presentation, I will review the mechanism of action of citrate, summarise the benefits and potential risks and outline the principles of citrate monitoring.