Family nursing is a specific area in the general context of nursing, emphasizing the interactions of the elements of the family, in a systemic perspective of care. Nursing intervention requires the use of models enabling the design of care geared to the collection of data and the planning of interventions. Therefore the Calgary Family Assessment Model (CFAM) is useful to understand the family in its multidimensionality. The study aimed to identify areas of nursing care in the family health context. Using the methodology of action research, the sample was formed by nurses of a Health Centre in Northern Portugal, using the technique of group discussion. From the results emerged a reconstruction of the Care Model through the combination of the focus of the practice described in the International Classification for Nursing Practice with the concepts of CFAM. In this model co-built evaluative categories have been specified to define the areas of attention in the context of Family Nursing. We believe to be a first step in the definition of the knowledge in this specific area, as the aspects that influence health states, which determine the health nursing care, concern the knowledge of nursing.