The Swedish education system, with its network of state-funded independent free schools, has provided inspiration to other countries keen to emulate its historical success.
But in recent times, all has not been well in the Scandinavian country. An unprecedented slide in its performance in the latest Programme for International Student Assessment (Pisa) tests prompted education ministers to call on experts from the Organisation for Economic Cooperation and Development (OECD) to investigate what was going wrong.
And this week, as a report was released of the experts' findings, Andreas Schleicher, the OECD official who runs Pisa, blamed Sweden's situation on everything from low teacher salaries to excessive spending on keeping class sizes small.
Sweden's decentralised education system - which includes free schools - has also come under fire, along with the country's preference for child- centred, project-based learning.
Unveiling the document in Stockholm this week, Mr Schleicher said that teachers' relatively low salaries were less a consequence of lower education spending than of Sweden's insistence on smaller class sizes.
"High-performing education systems typically prioritise the quality of teachers and everything associated with this, such as salaries and professional evaluation, over class size," he said, adding that teaching needed to become a "more attractive choice" of career in the country.
Sweden spent more, at $95,831 (pound;57,453) per student, than its neighbour Finland, which continued to perform well in Pisa, he pointed out.
Mr Schleicher highlighted the fact that the percentage of top-performing students was "particularly low" in Sweden, a traditionally egalitarian society. "Your education today is your economy tomorrow, and it depends very much on people at the high end of the spectrum," he warned.
He also criticised the way that Sweden had decentralised education. "When you look at other high-performing systems that have a lot of local responsibility, they usually balance this with strong mechanisms to innovate in the system: helping schools to identify failures, helping schools to address them in a very systematic way," he said. "The stronger the autonomy and responsibilities at local levels, the more you do need a level of central capacity."
Sweden brought its schools under municipal control and then liberalised them in the early 1990s, hoping that the competition created by giving students the right to choose between free and municipal schools would drive improvements in quality.
This set-up provided the inspiration for the flagship free school policy launched by England's education secretary Michael Gove - a programme that has started to show cracks in recent months, with two high-profile school closures.
Mr Schleicher's comments come less than a year after Sweden's opposition leader Stefan Lofven said that allowing schools to be run for profit had turned the Swedish education system into a "Wild West" that would be impossible to bring back under state control.
At the launch of the report, Mr Schleicher also said that it was a myth that the project-based, student-centred learning approach favoured in Sweden fostered creativity.
"Swedish students do not show a high level of creativity," he claimed, pointing out that whereas 30 per cent of students in Shanghai reached the top level in maths, which required a strong ability to think creatively, only 3 per cent of Swedish students did the same.
Referring to school systems in Shanghai and South Korea, he added: "What may look like `traditional' learning may in fact be highly, highly effective. Actually, it's quite well aligned with what modern research tells us about effective teaching practice."
The OECD report backed up the conclusions of research published last week by Leif Lewin, a professor at Uppsala University, who argued that Sweden's move to give local councils control of primary and secondary schools in the early 1990s had been "a failure", leading to "a decline in academic performance", "increased inequality" and lower status for teachers.
According to Professor Lewin, the biggest mistake made by the government at the time was failing to win teachers over. "Those who had to implement the reforms were against it," he told TES. "The basic conclusion is that you must trust the teachers, you must have the teachers with you."
- Over the past decade, Sweden's Pisa performance has declined in all three core subjects from around or above the OECD average to below the average.
- More than a quarter of students in Sweden do not reach the baseline level of performance in maths. That proportion increased significantly between 2003 and 2012.
- The country's share of top performers in maths has roughly halved over the past decade. Its share of top performers in reading and science has also fallen, although to a lesser extent.