A decade ago, the Partnership for Maternal, Newborn and Child Health (PMNCH) was established to combat the growing fragmentation of global health action into uncoordinated, issue-specific efforts. Inspired by dominant global public-private partnerships for health, the PMNCH brought together previously competing advocacy coalitions for safe motherhood and child survival and attracted support from major donors, foundations and professional bodies. Today, its founders highlight its achievements in generating priority for 'MNCH', encouraging integrated health systems thinking and demonstrating the value of collaboration in global health endeavours. Against this dominant discourse on the success of the PMNCH, this article shows that rhetoric in support of partnership and integration often masks continued structural drivers and political dynamics that bias the global health field towards vertical goals. Drawing on ethnographic research, this article examines the Safe Motherhood Initiative's evolution into the PMNCH as a response to the competitive forces shaping the current global health field. Despite many successes, the PMNCH has struggled to resolve historically entrenched programmatic and ideological divisions between the maternal and child health advocacy coalitions. For the Safe Motherhood Initiative, the cost of operating within an extremely competitive policy arena has involved a partial renouncement of ambitions to broader social transformations in favour of narrower, but feasible and 'sellable' interventions. A widespread perception that maternal health remains subordinated to child health even within the Partnership has elicited self-protective responses from the safe motherhood contingent. Ironically, however, such responses may accentuate the kind of fragmentation to global health governance, financing and policy solutions that the Partnership was intended to challenge. The article contributes to the emerging critical ethnographic literature on global health initiatives by highlighting how integration may only be possible with a more radical conceptualization of global health governance.