Child custody and guardianship are legal terms which are sometimes used to describe the legal and practical relationship between a parent and his or her child, such as the right of the parent to make decisions for the child, and the parent's duty to care for the child.

Following ratification of the United Nations Convention on the Rights of the Child in most countries, terms such as "residence" and "contact" (known as "visitation" in the United States) have superseded the concepts of "custody" and "access". Instead of a parent having "custody" of or "access" to a child, a child is now said to "reside" or have "contact" with a parent. For a discussion of the new international standards, see parental responsibility.

Residence and contact issues typically arise in proceedings involving divorce (dissolution of marriage), annulment and other legal proceedings where children may be involved. In most jurisdictions the issue of which parent the child will reside with is determined in accordance with the best interests of the child standard.

Family law proceedings which involve issues of residence and contact often generate the most acrimonious disputes. While many parents cooperate when it comes to sharing their children, not all do. For those that engage in litigation, there seem to be few limits. Court filings quickly fill with mutual accusations by one parent against the other, including sexual, physical, and emotional abuse, brain-washing, parental alienation syndrome, sabotage, and manipulation. It is these infrequent "super-heated" custody battles that make the news and sometimes distort the public's perceptions as to the prevalence of such disputes and the adequacy of the court's response.

Members of the fathers' rights movement challenge the adequacy of the courts' responses based on the best interests of the child standard, which they describe as highly subjective and based on the personal prejudices of court-appointed child custody evaluators.