The UK's highest court is to rule on a legal challenge to the Scottish Government's proposals to appoint a named person for every child.
The scheme was approved by Holyrood as part of the Children and Young People (Scotland) Act 2014 but an appeal against it has been mounted by four charities and three individuals.
Under the measure, a single point of contact, such as a teacher or health visitor, would be assigned to look out for the welfare of children under 18.
The named person is required to exercise statutory functions, including providing advice, information or support where appropriate to promote, support or safeguard the wellbeing of the child or young person.
Scottish ministers say the service will act as a safety net to help families and children if they need it while opponents argue the move breaches the human rights of parents.
Those involved in the No To Named Persons group (NO2NP) previously lodged a petition for a judicial review at the Court of Session in Edinburgh, Scotland's top civil court, challenging the lawfulness of the provisions but it was rejected.
Judges then refused a later appeal against the decision.
An appeal was then heard before a five-strong panel of justices at the Supreme Court in London in March.
The Supreme Court will announce its decision on Thursday.
The court has been asked to decide whether the provision is compatible with fundamental common law rights and the European Convention on Human Rights, and laws on the sharing and disclosure of information from Westminster and the European Union.
The group challenging the legislation is spearheaded by The Christian Institute, Family Education Trust, The Young ME Sufferers (''Tymes'') Trust and Care (Christian Action Research & Education) lodged a petition alongside three individual people.
Several children's charities and professional organisations have put their name to a letter in support of the legislation.
A Scottish Government spokeswoman said at the time of the Supreme Court hearing: "This Government is absolutely committed to ensuring that all our children get the best possible start in life. Getting It Right for Every Child, which includes the named person service, is an investment in all our futures.
"It aims to change the culture and practice of professionals, giving them the confidence, skills and knowledge they need to put children's needs and interests at the heart of services and support they provide for families."