The Strange Situation Test was the first way Attachment Style or Attachment Theory categorized people.  The first test identified three distinct groups, the dismissive avoidant, the preoccupied anxious, and the secure attachment style.  This was done by observing common reactions to many events.  At a later time the fearful avoidant, also known as disorganized attachment was categorized.   Attachment Styles help in current and future relationships. 

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