Introduction: Increased awareness of the importance of mental health for global health has led to a number of new initiatives, including influential policy instruments issued by the World Health Organization (WHO) and the United Nations (UN). Method: This policy brief describes two WHO instruments, the Mental Health Action Plan for 2013–2020 (World Health Organization, 2013) and the Mental Health Atlas (World Health Organization, 2015), and presents a comparative analysis with the Sustainable Development Goals (SDGs) of the UN’s 2030 Agenda for Sustainable Development (United Nations, 2015). Results: The WHO’s Action Plan calls for several specific objectives and targets, with a focus on improving global mental health governance and service coverage. In contrast, the UN’s Sustainable Development Goals include only one goal specific to mental health, with a single indicator tracking suicide mortality rates. Discussion: The discrepancy between the WHO and UN frameworks suggests a need for increased policy coherence. Improved global health governance can provide the basis for ensuring and accelerating progress in global mental health.