This article is one of the first of its kind to undertake empirical research into the engagement of a devolved government in a UN human rights treaty monitoring process. There is a lack of studies on this topic, even though the UK’s devolved nations have legislative competence and responsibilities to implement many obligations arising from several international human rights treaties, such as the UN Convention on the Rights of the Child (UNCRC). The article provides a case study to evaluate and compare how regional governments are accommodated in the treaty body system so that future monitoring processes accurately reflect the differences in implementation of UN treaties, or lack thereof, across different regions within the State. The potential impact of ‘under-representative’ State reporting is also examined. The article highlights that State Reports and the monitoring process should ensure accurate and reliable information on implementation in each nation of the UK and, more specifically, should ensure that the State delegation is composed of a balanced number of representatives from each nation, that delegation responses to Committee questions clearly indicate whether the reply relates to law, policy and practice in the UK as a whole or solely to a specific nation, and that delegation representatives have a full understanding of the division of responsibilities between the UK Government and the devolved governments.