Mike Jones, chief executive of the Association of MBAs, the London-based accreditation body, says that when people ask him what is the best business school in the UK he asks "best for whom?"

Mr Jones says that, in selecting a business school, students could talk to existing students at schools they are considering and look at league tables of performance. Yasmin Aulakh, 24, from India, selected Lancaster University Management School after inspecting UK league tables, while Oscar Salamanca, 30, from Mexico, also chose the same school after strong recommendation from friends.

Students, says Mr Jones, should also carefully consider a range of other factors. These include what they can afford; what sort of study they want, be it full-time or part-time; and the mix between theory and practice on the MBA programme.

For, while the core syllabus of good business schools is unlikely to differ significantly from one accredited school to another, there are differences in depth of faculty and emphases on the syllabus. Many of the older established business schools, which grew out of universities, place greater emphasis on theory, with case studies used for projects, while the newer business schools, many of which grew out of polytechnics, are more rooted in applied knowledge.

At London Business School, for example, students will be lectured by some of the world's finest business theorists while at Kingston Business School and Manchester Metropolitan University students' teachers will include successful local businessmen and women.

However, Mr Jones does have one very strong recommendation on quality - that students should select a business school that has been accredited by his organisation.

Accreditation by the Association of MBAs is the most widely recognised badge of a quality MBA programme in the UK. It is held by 35 of the 120 institutions in the UK conferring the MBA and about 50 business schools worldwide.

These include Insead, IMD in Lausanne, Institut d'Etude Politiques de Paris, SDA Bocconi in Milan and the Helsinki School of Economics and Business Administration. The benchmark measures MBA courses against criteria such as student experience, the quality of teaching and size of faculty, and calibre of students. Normally, students are expected to have an average of three years' work experience - a qualification not met by many schools which are not accredited.

There are other international benchmarks of quality. The two leading ones are the Equis standard, offered by the European Federation for Management Development (EFMD) and which assesses the quality of the whole institution, including its executive education, and that of the AACSB, the international association for management education, the US accreditation body.

Some 66 per cent of students studying in the UK attend a school accredited by the Association of MBAs - with Robert Gordon University's Aberdeen Business School the latest to be accredited. Initially, this was for a provisional one year period but this year the school won full five-year accreditation.

The Aberdeen Business School, part of the Robert Gordon University, is an interesting case study of how the Association of MBAs can work with a school towards accreditation. Two other business schools are currently working with the association in a similar fashion.

Aberdeen Business School started offering an MBA in 1993. Alex Mackay, director of the MBA programme, says: "We thought about accreditation very soon after establishing the MBA. The market is very competitive and very conscious of quality." The business school started talking informally to the association in 1997 and in 1998 applied for accreditation. However, the first visit resulted in provisional accreditation for one year only. Further full accreditation, for a five year period, was dependent on addressing a number of reservations identified by the accreditation panel. Robert Owen, accreditation manager at the association, says: "We could see great potential in its MBA but the qualification needed strengthening in a number of respects. So we went into a developmental mode with the school."

This process included one member of the assessment panel, Richard Thorpe, of Manchester Metropolitan University, acting as a mentor. He, for example, talked to staff at Aberdeen about what he believed constituted a quality MBA.

Issues raised by the accreditation panel for consideration - and acted upon successfully by the school - included:

* Some students were transferring on to the MBA course at an accelerated entry point with only a Diploma in Management Studies. The association believes that only a DMS distinction can equip a student for MBA studies.

* There were insufficient links between teachers and those staff involved in pure academic work.

* There was insufficient focus on core subjects, with economics, for example, spread over several disciplines, leading, according to the association, to a lack of depth in teaching.

* There was insufficient international breadth - with the human resources elective, for example, weak on cross-cultural management issues.

Mr Mackay says that with Prof Thorpe's assistance the business school developed a programme of change during a 12-month period.

"This was not a box-ticking exercise. The association was very much interested in how we developed our syllabus and its delivery," he says.

"The process that we underwent was neither a tweaking nor a fundamental review of our MBA. Rather, it was a re-focusing, not just of the syllabus, but also of how it was informed." He says improved links, for example, were forged with the local business community and the academic and applied research centres within the school.

Accreditation, he says, does not mean standardisation. "I never felt the association was trying to standardise our MBA. There was room for diversity and the association sought to ensure that our business school had a strong relationship to the local business community and its particular needs."

The school, located at the heart of the UK offshore oil industry, is the only UK business school with a module in offshore management.

Mr Jones, of the Association of MBAs, says: "There needs to be a variety of consumer choices without diversity of quality."