An attachment is a strong, emotional bond between the infant and their primary caregiver, usually the mother. Various risk and protective factors affect the development of such an attachment, contributing to the attachment being ‘secure’ or ‘insecure’ (see Ainsworth’s Strange Situation, 1972, for further classifications of insecure attachment types).Risk factors may include the parent having depression (supported in a meta-analysis by Van Ijzendoorn et al., 1992), how busy the parent is, and how sensitive the parent is to their child’s needs. Another risk factor may be the infant’s own temperament – for example, if the child is aggressive, the parent may be influenced to use more insecure parenting techniques. This is an example of a biosocial risk factor interaction, as the child’s temperament is a biological factor that interacts with the parent’s social behaviour.