According to the Children Act 1989 PR is ‘all the rights, duties, powers, responsibilities and authority which by law a parent of a child has in relation to a child and his property’. PR only applies once a child has been born and does not apply while the child is In Utero. There is no legal limit to the number of adults who can have PR for a child. PR was the most significant new concept created by the CA1989 and replaced the concept of parental rights in Section 4 of the Family Law Act 1987.
PR was a response to legislative changes in 1987 which removed the concept of illegitimacy and thus threatened to give fathers automatic parental authority over their illegitimate children which had previously been held only by mothers. In its Second Report on illegitimacy the Law Commission recommended that fathers of non-marital children should only achieve parental authority through judicial scrutiny, to guard against ‘unmeritorious’ fathers. The 1989 Act was a compromise, whereby fathers could acquire PR either through judicial scrutiny or through agreement with the mother.
PR defines a parent’s obligations towards a child; it does not confer any right. In Re H-B (Contact)  EWCA Civ 389 the President of the Family Division, James Munby, said,
 … parental responsibility is more, much more, than a mere lawyer’s concept or a principle of law. It is a fundamentally important reflection of the realities of the human condition, of the very essence of the relationship of parent and child. Parental responsibility exists outside and anterior to the law. Parental responsibility involves duties owed by the parent not just to the court. First and foremost, and even more importantly, parental responsibility involves duties owed by each parent to the child.
In H v A (No. 1)  EWFC 58 Mr Justice MacDonald observed that  ‘A parent's rights, duties, powers, responsibilities and authority… are only derived from their obligations as a parent and exist only to secure the welfare of their children’; in a case in which a father’s obsessive urge to harm the mother was putting his children at risk it was therefore legitimate for a court to  ‘prescribe, to whatever extent is in the child's best interests and proportionate, the exercise by that parent of their parental responsibility.’
Mr Justice Wall provided a useful pocket guide to parental responsibility in a footnote to his judgment on A v A  EWHC 142. It is really important to understand this; abuse of these principles leads to endless unnecessary litigation:
1. Decisions either parent can take independently of the other without consultation or notification:
a) How the child is to spend his time during contact periods;
b) Personal care for the child;
c) Activities undertaken;
d) Religious and spiritual activities;
e) Continuing to take medicine prescribed by a GP.
2. Decisions either parent can take independently but of which they must inform the other:
a) Medical treatment in an emergency;
b) Visits to a GP and the reasons for them;
c) Booking holidays or taking the child abroad during contact time.
3. Decisions which must only be taken following consultation:
a) Selecting a school and applying for admissions;
b) Contact rotas during school holidays;
c) Planned medical and dental treatment;
d) Stopping medication prescribed by a GP;
e) Attendance at school functions (so the parents may avoid meeting each other wherever possible);
f) Age at which children are allowed to watch age-restricted DVDs and video games.