Bowlby suggested that attachments formed early in life have a significant impact on adult relationships. He proposed that during infancy, the Internal Working Model (IWM) is formed, which serves as a template for all future relationships, influencing our ideas about ourselves and others. The continuity hypothesis suggests that the IWM has a long term effect on our approach to relationships, showing that childhood does impact adult relationships. Shaver et al found that the type of attachment formed during childhood determines the nature of relationships sought during adulthood; for example, people who had insecure avoidant attacment tended to seek sex without love later in life. It has also been suggested that our approach to adult relationships is affected the by integration of three behavioural systems during infancy: attachment, care-giving and sexuality.