There is no one definitive set of behaviours that constitute parental alienation but research with both parents and children has revealed a core set of alienation strategies:

• a campaign of denigration against the targeted parent. The child becomes obsessed with hatred of the targeted parent in the absence of actual abuse or neglect that would explain such negative attitudes
• weak, frivolous, and absurd rationalisations for the depreciation of the targeted parent. The objections made in the campaign of denigration are often not of the magnitude that would lead a child to hate a parent, such as scraping their plate or serving horrid vegetables
• lack of ambivalence about the alienating parent. The child expresses no ambivalence about the alienating parent, demonstrating an automatic, reflexive, idealised support of him or her
• the child maintains that the decision to reject the other parent is his/her own. This is known as the "Independent Thinker" phenomenon
• absence of guilt about the treatment of the targeted parent. Alienated children will make statements such as, "He/She doesn't deserve to see me"
• apparently unconditional support for the alienating parent in the parental conflict
• borrowed scenarios. Children often make accusations towards the targeted parent that utilise phrases and ideas adopted wholesale from the alienating parent. And, finally,
• the hatred of the targeted parent spreads to his or her extended family. Not only is the targeted parent denigrated and avoided but so too are his/her entire family. Formerly beloved grandparents, aunts, uncles and cousins are suddenly avoided and rejected too