Definition
Attachment theory is the developmental framework, originated by John Bowlby and extended by Mary Ainsworth, that proposes infants are biologically predisposed to form a close emotional bond with a primary caregiver. That bond functions as a secure base — a source of comfort the child can return to and a launchpad from which to explore the world. The quality of this early bond shapes an internal working model of relationships that influences self-image, trust, and intimacy across the lifespan.
Ainsworth's Strange Situation experiment identified four attachment patterns observable in infants: secure, anxious-resistant, anxious-avoidant, and disorganised. These early styles correlate, though imperfectly, with patterns adults show in romantic and other close relationships.
Why it matters
How it works
The infant brain is wired to monitor proximity to a caregiver. When the caregiver is responsive, the infant develops the implicit expectation that distress will be met with comfort — a secure attachment. When the caregiver is inconsistent, rejecting, or frightening, the infant adapts strategically: amplifying distress to elicit attention (anxious-resistant), suppressing distress to avoid rejection (anxious-avoidant), or oscillating without strategy (disorganised). These strategies become the child's working model.
In adult life, the internal working model shapes whom we choose, what we expect, and how we behave under relational stress. Insecure styles tend to persist but are not destiny — corrective experiences with a trusted partner, therapist, or close friend can update the model over time. Therapies that explicitly target attachment patterns work by providing exactly such a corrective relationship.