Research on the harmful effects of institutionalization across child functioning domains, especially on infants and young children, is well documented, as is the capacity for recovery following family foster care (FFC) placement. Despite this, in Portugal in 2020, only 3% of all out-of-home children were in FFC. Seeking to respond to the European calls-to-action for deinstitutionalization, the 2019 Portuguese law has reinforced non-kinship FFC as the alternative care measure for children up to the age of 6. As a result, massive recruitment, training, and selection of foster families began in the Lisbon Area.This system shift to FFC is challenging – e.g., it requires highly specialized services to meet foster family and child needs, and thus ensure sustainability. Child Welfare Practice Models (CWPMs) can be part of the solution, by strengthening consistency and quality in child welfare (CW) practice. As Portugal was lacking a proper model, a new CWPM – i.e., Modelo Integrado de Acolhimento Familiar (MIAF; Integrated Model of Family Foster Care) – was recently developed, covers the FFC full continuum, from the recruitment, selection, assessment and training of foster families (module 1) to foster care placement and child transition to a permanent solution (module 2). After the promising results of a first pilot, this proposal proceeds with MIAF's ongoing initial implementation process, based on cutting edge literature on social innovation and process evaluation.Both process (i.e., fidelity) and outcome evaluations should precede effectiveness testing and full implementation of a CWPM, allowing for timely improvements. Research on process evaluation suggests that it takes time for an innovation to be adopted and that identification of the multi-level factors (e.g., caseworkers’ burnout, unsupportive leadership) that can act as barriers for the successful implementation of a CWPM is crucial. Especially for an innovation in FFC in Portugal, such as MIAF, where evidence ...