The field of global mental health (GMH) has undergone profound changes over the past decade. Outgrowing its earlier agenda it has performed a reflexive turn, broadened towards a social paradigm and developed new modes of knowledge production, all of which reshaped ‘mental health’ as a global object of knowledge and care, and the epistemic politics of the field. Drawing on long-term ethnographic fieldwork among GMH experts and recent agenda-setting publications, I discuss how GMH advocates and critical observers alike have created conceptual and practical middle-grounds between different forms of mental health knowledge – across culture, epistemic power, lived experience, policy platforms and academic disciplines – framing their dynamic encounters as dialogue, adaptation, participation, co-production or integration. Ultimately, I argue, GMH today is focusing less on establishing mental health as a universal problem than on managing its inherent multiplicity through alignment and integration across different bodies of knowledge. Global knowledge, so conceived, is fluid and malleable and produced in open-ended knowledge practices, governed by what I call ‘contingent universality’. It is not new that the concepts and practices of the psy-disciplines are malleable and multiple, internally and externally contested, rapidly changing over time and not easily transferrable across space. What is new is that within the increasingly heterogenous epistemic space of GMH, these features have become assets rather than liabilities. GMH knowledge achieves both global reach and local relevance precisely because ‘mental health’ can be many things; it can be expressed in a wide range of idioms and concepts, and its problems and solutions align easily with others, at many scales. These fluid and integrative knowledge practices call for renewed empirical, critical and collaborative engagement.