ABSTRACT Objective: To assess the influence of structural and developmental factors on family functioning. Material and Method: Analytical, cross-sectional study with 200 individuals from 100 Brazilian families. Data were collected with the instrument The Assessment of Strategies in Family-Effectiveness (ASF-E/Brasil); a form to characterize the participants, to identify the roles, the development cycle and a field diary to describe family arrangements. For analysis, data were evaluated for simple frequency, means and Spearman correlation coefficient (p) (p <0.05). Results: The effectiveness in family functioning was high in 82.0% families. The arrangement of nuclear families was > 50.0% and the predominant role was that of mother. More than 75.0% families were in more than one development cycle, with a predominance of the phase of "launching" their children. The cycle with the best mean value of effectiveness in family functioning was "Family with preschool children (older child between 30 months and 6 years old)". There was a significant correlation between all the arrangements and there was no correlation between roles and development cycles with the effectiveness of family functioning. Conclusions: The structural, developmental and functional assessment of the family showed the influence of the arrangements on family functioning.