Better policies, investments, and programs are needed to improve the integration and quality of maternal, newborn, and child health services. Previously, partnerships and collaborations that involved multiple countries with a unified aim have been observed to yield positive results. Since 2017, the WHO and partners have hosted the Quality of Care Network [QCN], a multi-country implementation network focused on improving maternal, neonatal, and child health care. In this paper, we examine the functionality of QCN in different contexts. We focus on implementation circumstances and contexts in four network countries: Bangladesh, Ethiopia, Malawi, and Uganda. In each country, the study was conducted over several consecutive rounds between 2019–2022, employing 227 key informant interviews with major stakeholders and members of the network countries, and 42 facility observations. The collected data were coded using Nvivo-12 software and categorized thematically. The study showed that individual, organizational and system-level circumstances all played an important role in shaping implementation success in network countries, but that these levels were inter-linked. Systems that enabled leadership, motivated and trained staff, and created a positive culture of data use were critical for policy-making including addressing financing issues—to the day-to-day practice improvement at the front line. Some characteristics of QCN actively supported this, for example, shared learning forums for continuous learning, a focus on data and tracking progress, and emphasising the importance of coordinated efforts towards a common goal. However, inadequate system financing and capacity also hampered network functioning, especially in the face of external shocks.