THIS paper briefly outlines the dilemma confronting assessment and certification authorities in ensuring comparability of end-of-school assessments and proceeds to outline approaches adopted in Victoria following the introduction of the Victorian Certificate of Education (VCE). In particular, a description is provided of a new system for maximising comparability of school-based assessments which was implemented for the first time in 1994. This system made use of a reference test (the General Achievement Test) to check on the reasonableness of schools' assessments and to identify those schools with unexpected results. If schools' assessments were within a specified tolerance band, the schools' assessments were automatically confirmed. If they fell outside the tolerance band, the schools' assessments were subject to re-marking by two external reviewers. This re-marking in turn led to a decision either to confirm or adjust schools' assessments. The paper concludes with some preliminary observations on the outcomes of implementing the new system.