A father from the Isle of Wight who took his daughter out of school for a family holiday has lost his legal battle in the Supreme Court. So what are the rules around term-time holidays and how have they changed in recent years?
Why did ministers crack down on term-time holidays?
With the cost of trips abroad rocketing during the school holidays, it is hardly surprising many parents are tempted to take their children away during term time.
But this obviously means pupils missing lessons, and the government says there is clear evidence doing so impairs children's attainment.
In 2012, the then Education Secretary, Michael Gove, said: "We need to do more to discourage holidays taken during term time: the rate of these absences in primary schools is double that in secondary schools."
Ministers were concerned that because of guidelines dating back to 2006, some parents mistakenly believed they were entitled to two weeks' annual holiday during term time as a right.
What did the guidelines actually say?
The Education (Pupil Registration) (England) Regulations 2006 said head teachers could grant leave of absence of up to 10 days for the purposes of a family holiday during term time in "special circumstances".
Head teachers could also grant extended leave for more than 10 days in "exceptional circumstances".
And the government said it had long recognised schools were experiencing problems with parents using this threshold as a right, rather than as a rough guide for a particular sort of situation.
What changes did ministers make to the guidelines?
They removed all references to family holidays from the regulations and said head teachers could not grant any leave of absence to pupils during term time without "exceptional circumstances".
This came into force in September 2013.
They also highlighted and tightened the procedure for local education authorities fining parents for unauthorised pupil absences.
Under the 2006 guidelines, parents could be fined £60 for the unauthorised absence of a child, if it was paid within 28 days, rising to £120 if it was paid within 29 to 42 days.
In September 2013, the timescale for payment was reduced to 21 days at £60 and 28 days at £120 respectively.
The fines were to be levied by local authorities for absences in maintained schools, and by academies where absences were from academies.
What was the reaction?
Numerous polls of parents suggested the policy was not very popular, with some arguing they should be able to take term-time holidays if they were booked in advance, for a strict number of days and not at a crucial time.
The National Union of Teachers suggested there were important cultural and social benefits to going on holiday and that this should not become the preserve of the middle classes.
The Local Government Association agreed, saying the law was not really practical.
The LGA said families often struggled with the high cost of trips out of holiday time and called for a common-sense approach.
Nonetheless, between September 2013 and August 2014 almost 64,000 fines were issued for unauthorised absences, according to local authority data.
However, different LEAs appear to have taken quite different approaches to cases of unauthorised absence, and the government website invites parents to check with their own local authority if and when they may face a fine for the non-attendance of a child.
All clear then?
Well, not really.
The head teachers supposed to be making these decisions said they wanted detailed guidance on what constituted exceptional circumstances.
National Association of Head Teachers (NAHT) general secretary Russell Hobby said: "Head teachers already have discretion over the granting of absence during term time.
"They rightly prioritise learning over holidays."
But to clarify matters, the NAHT published guidance on how heads could arrive at a decision to authorise absence or not, adding there could be no absolute rules on this subject.
Term-time was for learning, it said, adding children and families already had 175 days off school, including weekends and school holidays, to spend time together.
An absence for the bereavement of a close family member, a funeral or important religious observances could be counted as exceptional, it said.
But if an event could reasonably be scheduled outside of term time, then it would not be normal to authorise absence, the guidelines added.
Heads would be expected to determine in advance the exact number of days a pupil may have away from school.
In the case of unauthorised absence, the decision to prosecute or seek a fine then rests with local authorities.
What are the rules elsewhere in the UK?
In Scotland there are no fines for parents who take their children on holiday in term-time.
But the Scottish government advises that schools will not normally give a family permission to take pupils out of school for holidays.
It is up to education authorities to decide sanctions for persistent truancy.
Likewise in Northern Ireland term-time holidays are considered unauthorised absences but there are no fines.
Parents who come before the courts for absenteeism are those who have allowed their children to truant over a long period.
In Wales families are allowed up to 10 days of term-time holiday at the head's discretion. In January Huw Lewis, the education minister for Wales, wrote to councils saying it was wrong to tell head teachers to ban all term-time leave.
His intervention followed a petition by parents last year against fines for taking holidays in term-time.