Analyses related to the Covid-19 pandemic have mainly addressed measures adopted in response to this event without paying attention to provisions included in the 2005 International Health Regulations which require States to develop predefined core capacities to prevent, control and provide a public health response to the international spread of disease. The legal architecture related to these obligations has, however, various shortcomings and States have largely failed to implement the required measures. Only recently has some practice been developed by the WHO to address these deficiencies, and further action is still required to finally implement this (neglected) cornerstone of the global health system.