This paper describes elements of a thesis as part of requirements for an EdD (Doctorate in Education) at Queen’s University Belfast. The subject is assessment in early years (ages 4-6) Irish-medium [IM] primary schools in the north. It will analyse assessment practices in a sample of IM schools and units, with a focus on participants’ perspectives through the narratives of teachers and principals. The analysis is embedded in Lave’s socio-cultural framework of arenas and settings (1988). The data explains how practitioners address contradictions in assessment policy in their settings. The data show the interactive nature of early years IM assessment and the value of teacher observation but also the paucity of appropriate assessment tools for foundation stage IM pupils compared to those available in English. The study cautions against the practice of assessing pupils educated through the medium of Irish by tools designed and normed for monolingual pupils.