This article analyzes implementation, compliance, enforcement and reform of the Espoo Convention and Strategic Environmental Assessment (SEA) Protocol in the European Union (EU). It focuses upon suggested improvements and perceived gaps in transposition and, where gaps are real, considers how best to remedy them. It examines the reform of EU secondary law needed to improve the process and ensure compliance with these international treaty obligations, and associated EU caselaw. The judicial technique of invoking direct application and effect of international agreements in the EU is considered as an impractical means of addressing any perceived unimplemented provisions of the Espoo Convention and SEA Protocol in the absence of full transposition. It is concluded that without adequate law reform to meet any outstanding international legal obligations, the EU may be challenged via the treaty non-compliance procedures.