How might international society serve as an ontological security provider? Ontological security studies sees societies as both containers of anxiety and providers of security, but there is little research on how international society relates to this. Any answer to my question is further complicated by multiple takes (Lacanian, Kleinian, and Winnicottian) on the way the subject secures its self. I demonstrate how this multiplicity is accommodated by the conceptual heterogeneity of the ‘English School’ and offer three separate answers. Lacanian theory suggests a ‘pluralist’ international society can mitigate ontological insecurity because its institutions encircle ‘the lack’ that constitutes (collective) subjectivity. Kleinian theory supports the institutions of a ‘thin solidarist’ international society because it demonstrates how the collective action needed to protect the legal rights that recognise and secure the (collective) self does not necessarily cause anxiety. Drawing on Winnicott, Honneth argues that the (collective) self can only be fully secured if the institutions of a ‘thick solidarist’ international society go beyond legal recognition to socially esteem the contribution the subject makes to realising the common good. The analytical framework is applied to interpret and respond to Russia’s invasion of Ukraine, offering a timely intervention into debates on a post-liberal international order.