The best interests of the child refers to the factors most courts consider when making decisions on child custody and visitation rights.

These factors may include the needs and circumstances of the child (happiness, security, mental health, emotional development, educational opportunities, special needs, siblings, religious and cultural considerations, continuity and stability, child’s wishes) and the circumstances of the parent or caregiver (relationships, living arrangements, history of abuse, mental health, physical health, financial resources, substance abuse).

There is generally a presumption that it is in a child’s best interests to have a relationship with both of the child’s biological parents—unless one or both of the parents are shown to be unfit parents.

In Arizona, the 'best interests of the child' is the standard used by courts to make decisions regarding child custody and visitation rights. Arizona law outlines specific factors that courts must consider when determining what arrangements will serve the child's best interests. These factors include, but are not limited to, the child's emotional and physical needs, the child's adjustment to home, school, and community, the relationship between the child and each parent, the parents' ability to provide for the child, any history of domestic violence or substance abuse, and, if the child is of suitable age and maturity, the child's wishes. Arizona law does indeed presume that it is beneficial for the child to maintain meaningful and continuing contact with both parents, unless there is evidence that a parent is unfit. This presumption can be overcome if one or both parents are shown to be unfit due to reasons such as abuse, neglect, or inability to provide proper care for the child.