The first experience of public-private partnership in the Spanish National Health System. In addition to the need to coordinate two levels of health care (primary/specialised), two models of human resource management (public/private) had to be coordinated. To illustrate this complexity, the group of midwives in the health area has been taken, analysing their relational patterns through the methodological approach of Social Network Analysis. In terms of results, out of a population of 31 midwives, those of the public model occupy peripheral positions and cooperate poorly, both internally and externally. However, those of the private model constitute a cohesive subgroup, which proves to be both a strength and a weakness. Midwives in primary care and in the private model bridge subgroups. Therefore, the presence of two management models determines the efficiency of maternal care rather than the division of care into two levels.