The relationship between politics and public health is increasingly evident as governments throughout the world vary in their acceptance and implementation of technical guidance in the response to the SARS-CoV-2 pandemic. This paper reports a qualitative study of public health policies for Covid-19 in Northern Ireland (NI) and the Republic of Ireland (RoI) across a timeline emphasising the first wave of the pandemic (February to June 2020). Inter-jurisdictional commitments for health as contained in the Good Friday Agreement provide a framework for cooperation and coordination of population health on the island of Ireland. This study of north-south cooperation in the response to Covid-19 applies ten indicators from the Oxford Covid-19 Government Response Tracker (OxCGRT) codebook to establish if cooperation and policy alignment of key public health measures are evident in the Northern Ireland Assembly and Government of Ireland responses. The study concludes that notwithstanding the historical and constitutional obstacles to an all-island response to Covid-19, there is evidence of significant public health policy alignment brought about through ongoing dialogue and cooperation between the health administrations in each jurisdiction over the course of the first wave of the pandemic.