Attachment refers to the affectionate bond between individuals that provides emotional closeness and endures over time and space. It offers a safe base and supports psychological, physical, cognitive, and moral development from infancy through adulthood. Attachment behaviors signal a child's need for care and protection. Patterns of attachment include secure, ambivalent, avoidant, and disorganized. While concepts of attachment are universal, aspects vary across cultures. A lack of attachment can cause difficulties relating to others, developing social skills, caring for others, and following rules. Separation and loss involve stages of shock, denial, anger, bargaining, sadness, and eventually resolution.