There has been much public discussion about church-controlled schools north and south and the potential issues involved if constitutional change was to occur. However, there has been far less debate about Northern Ireland’s use of academic selection and its impacts. To fill the research gap in this area and based on a review of the literature on academic selection, coupled with interview data gathered from principals in both the primary and post-primary sectors, from both selective grammar schools and nonselective secondary schools in Northern Ireland, this research reports on the advantages, disadvantages and perceptions of academic selection in Northern Ireland. Evidence derived from this research suggests that participants, in line with the literature, acknowledge that there are benefits to academic selection for some students and schools. However, the vast majority were also of the view that this advantage comes at a significant disadvantage for the majority of the student population before and after the selection process has occurred. This paper calls for the cessation of academic selection in all of its unregulated shapes and forms in Northern Ireland as has occurred in other jurisdictions.