Since its inception in the US in the 1960s, the Master of Business Administration has developed to become the world's most popular postgraduate business qualification.
Last year about 9,000 MBAs graduated in the UK, many of them health service managers and other public sector professionals.
They now have a wide range of courses to choose from:
general MBAs, courses aimed at the public services, or courses specialising in health.
Peter Calladine, education services manager at the Association of MBAs (AMBA), which accredits MBA programmes and promotes the qualification, says specialist MBAs remain popular.
'The courses are pretty stable. Some disappear, of course, but new specialised MBA programmes are being offered all the time. '
The biggest change in recent years - and one that looks set to continue - is a demand for more flexible ways of learning.
'It used to be that MBA courses were run, say, twice a week on Tuesday and Thursday evenings, ' says Mr Calladine.
'But It is difficult for busy managers to commit themselves to something as tightly scheduled as that.
More and more are looking for modular, part-time or distance-learning courses. '
He predicts there will be a growth in Internet MBAs, although it may be some time before really credible ones are on offer. And they will not appeal to everyone, Mr Calladine adds.
'Many MBAs say that half the knowledge gained on a programme is a result of sharing experiences with other students. Completing an MBA on the Internet will be no substitute for this interaction. '
These trends chime with the experience of two NHS managers who have pursued the MBA route.
Nigel Woodcock, acting chief executive of North Lakeland Healthcare trust, is half way through a new Master in Public Administration (MPA) programme launched by Warwick University Business School last year.
Warwick claims the course is designed to 'make a major contribution to the modernisation and improvement of government and the public services'.
Jean Hartley, MPA academic director, says it 'did a lot of research' and concluded that many of the existing courses in public administration in the UK are 'seriously out of date'.
'Some courses have failed to take account of the deep structural changes that have taken place in the political, economic, social and technological context of public services over the past five to 10 years, ' she says.
'They are out of touch with the complex realities facing public policy-makers. '
The new MPA is delivered over three years. Nine core, compulsory modules and four optional electives cover areas such as leadership and management capacity, visioning and value creation.
It specifically looks at managing inter-relationships with voluntary agencies and the private sector and brings together people from across the public services - the NHS, local government, armed forces and police.
There are also international electives - in the US, looking at comparative public policy and aspects of globalisation in conjunction with the Kennedy School of Government at Harvard University, and in Brussels, examining policy-making in the European Union.
Mr Woodcock says: 'I looked at all the MBAs available around the country, but none of them addressed the new public sector modernisation agenda.
'The Warwick MPA is tailored to that. It gives me unprecedented access to current policy-making and thinking. '
The standard of teaching, the case studies and the speakers, including top-level policy-makers and Cabinet ministers, have all been excellent, he adds.
And 'you also have a greater understanding of how to make better working relationships with the rest of the public sector generally'.
North Lakeland Healthcare trust hit the headlines last year when stories surfaced of abuse of elderly patients with dementia at the former Garlands Hospital.
Several senior members of staff were disciplined and the trust became the focus of the Commission for Health Improvement's first 'hit squad' investigation. Mr Woodcock was seconded to take over at the beleaguered trust in advance of a damning CHI report.
He is now involved in implementing the report's recommendations and preparing for the reconfiguration of services.
He would like to pursue his career at the trust but, if this does not happen, the MPA will give him 'a blue-chip qualification with international recognition'.
'Quite a few of us see it as giving us a foot-hold in a new range of career prospects over the next few years, ' he says.
Warwick University's general MBA, however, did not live up to the expectations of Stefan Cantore, chief executive at Mid-Sussex trust.
He found it 'too academic and overloaded with statistics', and after a year gave up to study with the biggest provider of MBAs in the country, the Open University Business School. This meant he could study by distance learning, and he appreciated being able to take the course at his own pace. He completed it in five years, having taken a year out to complete a counselling course.
The OU Business School MBA, which can be completed in three years, is built around a senior management block, a compulsory course in strategy and three electives covering issues such as finance, people, innovation and - a new element - communications and knowledge creation.
'The course really connected with my day-to-day work, ' Mr Cantore says. 'My colleagues all noticed a difference. I came back with new perspectives and new ideas I wanted to try out. '
Despite the distance learning, Mr Cantore found there were plenty of opportunities to network with other MBA students.
Tutor groups met locally at least once a month and attendance at week-long summer schools was expected.
The course 'really brought home the fact that the NHS offers the most significant management challenge in the country at the moment', he says. 'The NHS is an exciting, challenging environment.
The course reinforced that and boosted my confidence, recognising that my role is worthwhile. '
Mr Cantore has had two promotions since graduating - to deputy chief executive and then chief executive.
But it is essential to have absolute commitment to studying, he says. 'You have to spend a great deal of your own time working on it.
'You have to keep in mind the purpose of it and you need a clear vision from the outset, otherwise you will fall by the wayside. '