Now the Chancellor is backing the concept with cash.
By 2007, schools in England will have nearly pound;1 billion a year to spend on personalised learning I whatever that means.
Unlike other major developments in education, the concept does not comes from academics or teachers. Instead, it emerged almost entirely through ministerial speeches.
Tony Blair and his education ministers see it as part of new Labour's idea to revitalise public services by making them more responsive to individual needs, and they have been pushing for it since autumn 2003.
Think-tanks, academics and unions have tried to fill in the gaps and decide how it might work in practice. Now Gordon Brown, the Chancellor, has handed the initiative to heads with an unexpected windfall due to land in school bank accounts in September.
For schools unsure how to spend the money, the Department for Education and Skill's website suggests: "Some children need extra help, support and encouragement to get the basics right; others need greater stretch and challenge to make the most of their potential.
"Personalisation is about recognising that - so that schools can and do tailor their teaching and the wider support they offer to their pupils so that they can meet all their different needs."
In an interview with The TES, Ruth Kelly said of personalisation: "It is about leading-edge practice, it's about learning from international evidence about what works. Ultimately it's about mixing large group teaching with catch-up support for pupils falling behind, stretch for the more able and using technology more so that children and their parents can have links direct to schools."
For heads who wonder how this differs from what any good teacher would do, the department gives examples. The extra money could go on, for example, catch-up literacy and numeracy classes to visits from professional writers or theatre groups, and extending school hours. But it also stresses that it is for individual schools to decide what best suits its pupils.
John Dunford, general secretary of the Association of School and College Leaders, welcomes this lack of prescription. "It is right for the Government to be able to define the concept but leave it to the profession to determine what it means in practice," he said.
In fact, because the new money is not ring-fenced, schools do not actually have to spend it on personalised learning. But Mr Dunford says that as schools can define the concept in so many ways, most of their existing spending could fit under the personalised learning banner anyway. Pressed for examples of items that would not squeeze under that banner, he volunteers "heating and lighting".
More detailed guidance may emerge from a new review, headed by Christine Gilbert, chief executive of Tower Hamlets, London.
Unlike other standards grants, which are allocated according to pupil numbers, a "significant proportion" of the new money is to be targeted at schools where pupils are struggling or come from deprived homes.