Countervailing duty review ensures continuation only while subsidisation causing injury persists, with authority-initiated or requested reassessment. Review of countervailing duty requires the designated authority to reassess continuation where subsidisation causes injury, on its own motion or on a substantiated request. Definitive duties are time limited but may be extended if expiry would likely cause continuation or recurrence of subsidisation and injury; reviews must be completed within prescribed timeframes and applicable procedural rules apply mutatis mutandis.