Improving the calibre of the teachers joining the profession is not a "silver bullet" for raising educational standards and student attainment, a renowned global education expert has claimed.
Pasi Sahlberg, a leading campaigner and government official in Finland - a country that is consistently ranked among the top performers in international league tables - this week insisted that luring high-flying young people into teaching would not lead to success.
The warning comes at a time when many countries, desperate to improve their league-table positions, have explicitly focused on attracting the most talented graduates into the classroom.
England's education secretary Michael Gove has spoken of the importance of enticing "the brightest and the best" university-leavers into the profession, while his US counterpart, Arne Duncan, has also stressed the need to "transform the teaching profession and ensure that the next generation of teachers is the very best we can offer our children".
But Mr Sahlberg said that the emphasis on better teachers was misplaced. "We need good teachers, but I'm not sure we need superstar teachers," he told TES at the World Innovation Summit for Education (Wise) in Qatar. "I'm not convinced you can enhance your teacher community to the point that it will make a real difference (to education) standards. Just trying to get smarter people into teaching doesn't make a difference."
His comments come as debate rages in England over whether all teachers should have formal qualifications.
In the most recent Programme for International Student Assessment (Pisa) league tables, Finland was ranked third in the world for reading, sixth for maths and second for science. In a survey of adult skills published last month by the Organisation for Economic Cooperation and Development (which also runs Pisa), it fared even better, coming second only to Japan in both literacy and numeracy.
The idea that teacher quality is the key to improving schools has become increasingly widespread in recent years. Sir Michael Barber, who was education adviser to former British prime minister Tony Blair when he was in office, wrote in a highly influential report for the McKinsey consultancy: "The quality of an education system cannot exceed the quality of its teachers."
But although many observers have attributed Finland's enviable reputation to the strength of its teaching workforce, Mr Sahlberg told the summit in Doha that the idea of teacher quality as a "silver bullet" was wrong. Finnish teachers were no better than their counterparts in other countries, he added.
This is despite the fact that in Finland, only around one in 10 applications to primary school teacher training is successful.
"Many people seem to conclude, 'If only we had the teachers you have (in Finland), everything would be fine,'" he said. "There's this theory that (all you need is) a Finnish building, Finnish curriculum and Finnish teachers, but I think a lot of this success comes ... through communities and parents outside school. (Finnish students) are happy and healthy and secure and loved kids, most of them. If you have that kind of privilege in your society, it's no wonder that things go well.
"If you want to be a champion in football, you don't necessarily need to have all the best players. It's enough to have good players, if they're well coached and there's a mission, a vision to follow."
Mr Sahlberg said that most Finnish teachers were "pretty good". "But I've seen similar teachers in Canada, England, Ireland, Singapore, Australia, Germany and the other Scandinavian countries, and it's very difficult to see (that) these teachers really are much worse," he added.
Schemes such as Teach First in the UK and Teach for America in the US have won plaudits from politicians for recruiting more high-flying graduates into teaching. A recent research project for Teach First concluded that the initiative had raised exam results in the schools where it operates.
But a focus on exam results, as well as the move to create competition between schools, in countries such as the US, Sweden and the UK had served to "toxify" education rather than boost attainment, Mr Sahlberg argued.
"Autonomy, freedom and independence (for teachers) must be in place. Competition goes against many of these things. When schools begin to compete, they are not very keen to share what they do with anybody else," he said. "In Finland, it's all about the team, how (teachers) have a sense (that) 'we are all doing this together'. Somehow, we are able to empower, upgrade and improve them. I haven't really seen that in other places."