Hostile Aggressive Parenting (HAP) is defined as : A general pattern of behaviour, manipulation, actions or decision-making of a person (usually a parent or guardian) that either directly or indirectly; 1) creates undue difficulties or interferences in the relationship of a child with another person (usually a parent or guardian) involved with the parenting and/or rearing of the child and/or, 2) promotes or maintains an unwarranted unfairness or inequality in the parenting arrangements between a child’s parents and/or guardians and/or, 3) promotes ongoing and unnecessary conflict between parents and/or guardians which adversely affects the parenting, well-being and rearing of a child.

Hostile-Aggressive Parenting is most apparent in child-custody disputes and is used most often as a tool to align the child with one of the parents during litigation over custody or control of the child. However, HAP can be present in almost any situation where two or more people involved in a child’s life are at odds with each other over how a child may be raised or influenced by the parties. HAP can be present to some extent even when couples are still living together.

Although Hostile-Aggressive Parenting is often confused with Parental Alienation Syndrome (PAS), a term coined by Dr. Richard Gardner, HAP and PAS are not the same. HAP refers to the behaviours, actions and decisions of a person, whereas, PAS relates to the psychological condition of the child. In the vast majority of cases HAP is the cause of PAS.

Hostile-Aggressive Parenting is not limited to the biological parents but also applies to any guardian - grandparents, extended family members, daycare providers and to any other person who may be involved in caring and rearing of a child. In some cases, it may even involve a parent in dispute with the child’s grandparents, sometimes the parent’s very own parent! Any form of interference to a normal, healthy relationship between a child and a person (most often one of the parents) caused by another person or agency having some control or influence over the child, is wrong and ultimately causes emotional and psychological harm to the child. Throughout this document the word “parent” shall be considered synonymous with “guardian”.

Hostile-Aggressive Parenting is a very serious and damaging form of abuse and maltreatment that parents and even other family members can engage in. HAP is most often identified in individuals with controlling and bullying personalities or those with mild to severe personality disorders. HAP can be a factor in all types of parenting arrangements including sole maternal custody, sole paternal custody and joint custody. Interestingly, it is sole custodial parents who are most often reported to practice Hostile-Aggressive-Parenting, especially in its most severe form.

In general, parents exhibiting Hostile-Aggressive-Parenting have not succeeded in getting on with their own life and remain, instead, controlled by their negative emotions and continue to exercise power and control over their ex-spouse's life, their ex-spouse's parenting and to a large extent, over the children of the relationship as well. HAP parents will blame everyone else except themselves.

High degrees of conflict during custody settlements and litigation are almost sure signs in these affected families. Hostile-aggressive parents are unable to appreciate the needs of their child and in many cases view their child as a possession belonging to them and no other persons have any right to the child, especially not the child’s other parent or other persons that the HAP parent does not like. Hostile-aggressive parents will use the child as a weapon against the other spouse and family members whenever they have the opportunity. A parent engaged in Hostile-Aggressive Parenting will also take comfort in that the community in general will choose not to get involved, probably because they don’t know what to do. Angry and vindictive HAP parents are often able to bring a reign of terror and revenge on to a non-custodial parent and their family, their goal being to get them out of the child’s life or at the very least to severely damage their child’s relationship with the other parent and other parent’s family.