In recognition of the role of reproductive health in individual and national development, the Responsible Parenthood and Reproductive Health (RPRH) Law of 2012 was passed in the Philippines after 30 years of opposition and debate. Seven years later, this article examined the cohesiveness of national multi-sectoral governance among state and non-state actors and identified challenges in coordination as part of the first comprehensive evaluation of the landmark policy. Using a qualitative intrinsic case study design and guided by the World Health Organization’s systems checklist for governing health equity as our theoretical perspective, we conducted 20 semi-structured interviews with national implementers from health agencies (n = 11), non-health agencies (n = 6) and non-state actors (n = 3) that included civil society organizations (CSOs). Key themes identified through thematic analysis were supported with document reviews of policy issuances, accomplishment reports and meeting transcripts of the RPRH National Implementation Team (NIT). The study found that despite aspirations for vibrant multi-sectoral coordination, the implementation of the RPRH Law in the Philippines was incohesive. National leaders, particularly the health sector, were neither able to rally non-health sector actors around RPRH nor strategically harness the power of CSOs. Local resource limitations associated with decentralization were exacerbated by paternalistic financing, coordination, and monitoring. The absence of multi-agency plans fostered a culture of siloed opportunism, without consideration to integrated implementation. This case study shows that for neutral policies without conflicts in sector objectives, the interest and buy-in of non-health state actors, even with a national law, cannot be assumed. Moreover, possible conflicts in interests and perspectives between state and civil society actors must be managed in national governance bodies. Overall, there is need for participatory policymaking and health-sector advocacy to set health equity as an intersectoral goal, involving subnational leaders in developing concrete action plans, and strengthening NIT’s formal accountability systems.