["Global Networks, Volume 22, Issue 3, Page 397-412, July 2022. ", "\nAbstract\nAlthough existing studies have documented the capacity of migration city networks (CNs) to mobilize on the vertical/intergovernmental dimension, there is less evidence of how CNs can contribute to scaling up network governance with societal actors beyond local jurisdictions and favour the emergence of multilevel governance arrangements. In this article, I aim to contribute to deepening our understanding of migration CN horizontal state‐‐society relations by throwing new light on how CN leaders’ agendas affect the policy actions undertaken by two migration CNs in Europe and one in the United States. Evidence shows that migration CNs engage differently with non‐public actors depending on agendas that reflect the aims of their leaders. These agendas can be more or less conducive to scaling up migration network governance. When horizontal/state–society relations are conceived as subordinate to vertical relations, lobbying and political advocacy prevail with little room for the emergence of multilevel governance.\n"]