Inspired by legislation passed by the French government in 1968 which made universities responsible for lifelong education, the summer of 1972 saw Pierre Vellas coordinating at the University of Toulouse a summer school for retired persons. Since the enthusiasm of the participants showed no signs of abating at the end of the programme, Vellas was inspired to establish a permanent late-life learning programme. Conceiving the term 'University of the Third Age' (U3A) for his project, Vellas launched the first U3A centre in Toulouse in February 1973 to anyone who had reached statutory retirement age. The curriculum focused on a range of gerontological subjects, although in subsequent years subject content became mainly in the humanities and arts. The Toulouse initiative struck a rich vein of motivation so that the idea quickly crossed international frontiers. By 1975, U3A centres were already established in Belgium, Switzerland, Poland, Italy, Spain, and Quebec in Canada.

As the U3A phenomenon gained increasing international recognition in continental Europe, it did not escape the attention of British educators. The first British U3A was established in Cambridge in July 1981, and quickly replicated in other cities and towns. The British version underwent a substantial change compared to the original French model, as it embraced a self-help approach based upon the principle of reciprocity and mutual learning, with the hallmarks of British U3As being a sturdy independence and anti-authoritarian stance. U3A directors rejected the idea of pre-packed courses for more or less passive digestion. and instead demanded a kind of intellectual democracy where all members would be expected to participate in teaching and learning. Rather than being incorporated within social sciences, education, or theological faculties at traditional universities, British U3As were founded in community settings that ranged from public halls to churches to personal residences. Although many contemporary U3A centres still follow either the French or British traditions, one finds other models. 'Culturally-hybrid' U3As include both Francophone and British elements. For instance, U3As in Finland use university resources, but then are essentially cooperative unions.

Although 'French-speaking' U3As in Quebec, Canada, form part of traditional universities, admission requirements are age-friendly by including occupational experience and self-taught knowledge. U3As in South America are typified by a strong concern for deprived and vulnerable older persons. Finally, U3As in China adopt a holistic perspective towards learning, and hence, are concerned with active citizenship, cultural consolidation, philosophical reflection, and bodily harmony. Of course, many U3As do not fit either of the above models. For example, U3As in Taiwan are neither attached to universities nor are they self-help organisations, but are managed by local authorities.