An accurate and functional system for grading acute liver allograft rejection is important for patient management, research, and communication, The Banff schema is a consensus document designed to provide an internationally accepted standard for this purpose, The aim of this study is to determine if application of the Banff schema would significantly alter the grading of acute liver allograft rejection compared with the Birmingham system. One hundred twenty-four post-liver transplantation biopsies performed by the Western Australian Liver Transplantation Service between 1992 and 1997 were retrospectively analyzed by a pathologist and a hepatologist. Each was supplied with a brief clinical history before applying the Banff and Birmingham criteria, Results were compared with each other and to the diagnosis made at the time of the biopsy, which was based on the European grading system. Rejection was diagnosed by the reviewers in 61 of 124 biopsy specimens according to the criteria of Snover, The Banff schema and Birmingham system agreed on the grade of rejection in 22 of the 61 biopsy specimens. The Banff schema elevated the grade of rejection in 39 specimens by an increment of one. In no instance did the Banff schema reduce the grade. Comparison between the Banff schema and diagnosis made at the time of biopsy showed agreement in 39 specimens, whereas the Banff schema elevated the grade in 15 specimens and reduced the grade in 23 specimens. In comparison to the Birmingham system, the Banff schema elevated the grade of liver allograft rejection in the majority of biopsy specimens, and this has the potential to alter clinical management with the adoption of the Banff schema or if the systems are used interchangeably. Copyright (C) 1999 by the American Association for the Study of Liver Diseases.