Last July, the Financial Times contained as a paid for insert, a glossy brochure offering citizenship-by-investment in the Caribbean. It was little different in style to the advertising one sees for mega yachts, expensive real estate, private jet charters, and other expressions of the so called 'good life'.

The document was produced by one of the many companies now selling Caribbean citizenship to the very wealthy, aiming to draw their attention, by suggesting how they might become 'a citizen of the world', and obtain a 'life saving insurance policy' through a second nationality.

It was about a parallel universe, far from the gritty reality of everyday life for most citizens of the islands concerned.

Despite this, such schemes have become an economic lifeline for most OECS nations, raising substantial revenue for the governments concerned. This is especially the case as most have begun to mature and be better policed as a result of international in relation to the security issues involved, and because experienced international selling agents want probity and better control to ensure commercial sustainability.

That said, citizenship-by-investment programmes remain controversial. Many in the region object in principle to the idea that nationality is something that can be sold; finding unacceptable the granting of rights or freedoms to those who have no historic or cultural affinity with the Caribbean.

Such concerns have, however, largely been set aside as the need to find rapidly new sources of revenue to fund budgets has now driven the development of such programmes in every independent OECS nation other than St Vincent.

The schemes, with some variations, revolve around the granting of citizenship and a passport for an investment of around US$0.4m plus fees in property, government bonds, or by way of a donation. There is usually no residence requirement. They provide a Caricom passport enabling visa-free travel to many parts of the world, including in most cases the UK, the EU's presently borderless Schengen area, and Canada.

In the past those most interested in Caribbean citizenship were wealthy Chinese and Russians, but as a result of growing pressure from the authorities in both countries there are signs that their numbers may now be diminishing. More recently the interest has been coming from an increasingly unstable Middle East, the former Soviet Republics, and Africa. In addition some OECS countries have begun to market to high net worth individuals in nations like Malaysia, Indonesia or other fast growing advanced developing economies.

For the Caribbean Governments concerned the sums can be substantial. In a recent statement to Parliament, St Kitts' Prime Minister, Dr Timothy Harris, said that he expected the country to earn some 33% or around US$74m of its annual revenue from such programmes. He also revealed that since 2005 when just 6 citizenships were granted, the number has risen steadily, with 2,296 citizenships granted in 2015. There were, he said, now 10,777 foreign nationals who hold St-Kitts Nevis Caricom passports, who either made a minimum charity donation of US$0.25m, or a real estate investment of US$0.4m, plus fees.

Antigua's programme is reported to now generate annually 25% of all government revenue and it is considering allowing citizenship to be passed on by adults to children without charge after five years. It says that it denies about 2 to 2.5% of applications.

OECS programmes have in the past been the subject of public criticism from the US and Canada in relation to the ability of nations to undertake the necessary due diligence about the background of individuals to whom passports are to be issued; a matter not helped by separate but continuing scandals about the issuing of diplomatic passports to individuals involved in alleged illegal activities.

Since then, most Caribbean citizenship programmes have put in place, usually with external support, mechanisms to address these issues, but there remain clear variations in the way programmes operate.

While officials in North America and Europe make clear they have no objection to well run citizenship-by-investment schemes given they have ones of their own, they say they remain concerned, suggesting the possibility of sanctions against any nation unable to ensure their programmes meet international requirements.

Notwithstanding, other conceptual and practical problems remain.

At a purely economic level, it is hard to understand why such schemes are not designed to be sustainable in ways that bring continuing income to the country concerned. Without any residency requirement there is no long term gain in the form of other taxes or fees. Moreover, in the absence in some cases of the equivalent of an independently controlled sovereign fund able to receive fees from citizenship, one-off income remains unrelated to long-term infrastructural, education or public health care needs.

Secondly, the willingness of some countries to grant citizenship to future generations as well as the applicant means that not only is there no long term benefit from the passport holder's descendants, but the issuing nation concerned has little or no idea about the identity or nature of growing numbers of future citizens.

Thirdly, the real danger remains that should it be discovered that a passport has been issued to someone who is on a criminal or terrorism watch list, ordinary citizens may face blanket requirements for visas where none previously existed.

There are also other problems requiring resolution. There is a lack of clarity in some nations about what donations - the preferred route for most applicants - are applied to; there is a plethora of sales agents globally and a need for the regulation of their activities; some countries do not have the capacity to deal adequately with the number of requests being made; few governments join up their promotional efforts with developers to try to encourage investments into productive real estate or tourism projects; high risk investment vehicles are being approved; in some nations opposition parties allege impropriety in relation to who benefits; and most schemes still lack real transparency.

As international views on monitoring money laundering and transparency evolve, and concerns grow about global security, it is likely that countries offering economic citizenship without greater transparency could become the subject of more intense international scrutiny. It would be wise for the region as a whole to consider carefully how best to balance the understandable desire to create new sources of government revenue, with the wider implications and reputational risk inherent in citizenship-by investment- programmes.

David Jessop is the Director of the Caribbean Council and can be contacted at Previous columns can be found at February 5th, 2016