The contribution of primary care to population health and health systems organization has been well documented, but some authors have highlighted that in Third World countries it has gained more ground in discourse than in facts and practices, with different possible configurations. The objectives of the current study were to evaluate and correlate organizational and local contextual characteristics to the degree of implementation of primary care in two municipalities (counties) in the State of Bahia State, Brazil, that had adopted the Family Health Program (FHP) as the system's central thrust. The research was based on two case studies with interwoven levels of analysis, using as the point of departure the underlying goal-image of primary care in the definition of criteria and standards for degree of implementation. The total scores for Municipalities A and B were 66 and 81, respectively (maximum total score = 100), while differences were observed between the urban and rural teams. The political and institutional contexts helped explain differences in the degree of implementation of primary care, but regardless of the municipal context, the study showed the emergence of organizational innovations closely related to the FHP.