Associations between preschoolers' attachment security, parenting behaviours (i.e. parent-child involvement, parenting consistency and co-parenting consistency) and parenting context (i.e. parents' internal working models (IWMs) and use of social support) were examined in a sample of 235 culturally diverse families. The authors predicted that parenting behaviours would mediate associations between children's attachment security and less proximal parenting context. Mothers and fathers completed questionnaires regarding their parenting behaviours, IWMs of adult relationships, their use of social support and an attachment Q-List to assess their children's attachment security. Parenting behaviours mediated the relationship between parenting context and children's attachment security. Findings support an ecological view of children's attachment security within a multilayered system. (Contains 2 tables and 1 figure.)