Transfusion-related acute lung injury (TRALI) is the leading cause of transfusion-related morbidity and mortality world-wide. Although first described in 1983, it took two decades to develop consensus definitions, which remain controversial. The pathogenesis of TRALI is related to the infusion of donor antibodies that recognize leucocyte antigens in the transfused host or the infusion of lipids and other biological response modifiers that accumulate during the storage or processing of blood components. TRALI appears to be the result of at least two sequential events and treatment is supportive. This review demonstrates that critically ill patients are more susceptible to TRALI and require special attention by critical care specialists, haematologists and transfusion medicine experts. Further research is required into TRALI and its pathogenesis so that transfusions are safer and administered appropriately. Avoidance including male-only transfusion practises, the use of leucoreduced components, fresher blood/blood components and solvent detergent plasma are also discussed.