The use of MTX for GVHD prophylaxis may be associated with significant toxicity, including hepatotoxicity, graft failure and mucositis. Folinic acid may be involved in the amelioration of MTX toxicity. There is, however, no consensus regarding its use. A survey was conducted in Australian and New Zealand transplant centres (n=22) regarding the use of folinic acid following MTX in the transplant setting. Of 18 participating transplant centres, 12 (66%) used folinic acid following MTX--8 (44%) routinely and 4 (22%) only in the presence of significant mucositis. Those centres that did not use routine dosing of folinic acid post transplant chose not to do so on the grounds that they believed that it was not efficacious or may increase the risk of GVHD. Grading of mucositis was inconsistently done. There is wide variation in the use of folinic acid following HSCT. Folinic acid is infrequently used in the adult transplant setting or is used after mucositis is already apparent, practices that appear to run counter to available clinical evidence and to pharmacological data. Further research is required to conclusively determine whether folinic acid has any benefit in the post-BMT setting.