Transferred from the ownership of the Protestant churches after Partition, N. Ireland's Controlled schools have long suffered from a lack of collective identity, representation and ethos. It is envisaged that these issues will be ameliorated by the introduction of the Controlled Schools' Support Council (CSSC), whose work is underpinned by a Vision Statement for the ethos of the sector. This study investigates the under-explored area of the Controlled Sector and its ethos, whose values underpin it and how these values reflect its schools and stakeholders. The research of ethos is viewed through the lens of policy and applies Ball's (1997) trajectory approach in considering the potential impact of the CSSC's statement upon the sector's ethos. Employing exploratory and embedded approaches (Cresswell and Plano Clark, 2007) to mixed-methods data collection, a large-scale survey of Controlled principals complemented semi-structured interviews with a representative sample of policy-makers and principals. The study found a fragmented, unconnected and unsupported sector, which, although linked to Christian values, is uncertain in articulating what it is, does and stands for. It found a warm welcome for the CSSC, for continuing and increased church involvement, for the Christian values espoused in the Vision Statement, believing that it will not disenfranchise those who hold other worldviews, and for the statement as a basis for a collective ethos underpinning schools' individual ethoi. In addition to new insights on the sector, this study adds to the body of knowledge on ethos, building on the claim that ethos needs connecting words to make it intelligible (Allder, 1993) by proposing that there are eight terms most frequently associated with, confused with, or substituted for ethos and that, collectively, these interconnect to distinguish it more clearly. It also concurs with Donnelly (2000) and McLaughlin (2005) that ethos is found in the 'gap' between intended and lived, but concludes that this gap can be significantly narrowed in conceptualising ethos at the intersection of these eight interconnectors, proposing an ethos test which identifies the ethos through the characteristics of each. In isolating the current attributes of the Controlled Sector's interconnectors, and using the findings to suggest how these might change in light of the CSSC and Vision Statement, the test showed that a different and more positive ethos might result.