After Russian tech entrepreneur, Pavel Durov, was fired by the popular social-media company he founded, he vowed never to return home. “I’m out of Russia and have no plans to go back,” he told TechCrunch in April, accusing Russian authorities of silencing political dissent on VK.com.

But even before this run-in, Mr. Durov had an escape route in the form of a passport from the tiny Caribbean country of St. Kitts and Nevis.

The twin-island nation of roughly 55,000 people grants citizenship in exchange for either a contribution of $250,000 or more to its Sugar Industry Diversification Foundation or the purchase of approved real estate worth a minimum of $400,000.

Selling passports is a way for the cash-strapped nation to raise money and has helped transform an economy once dependent on sugar cane. But as the program has grown, so have allegations of abuse. Just last month the US Treasury Department raised concerns that St. Kitts had issued passports to three Iranian men who were using the documents to allegedly help Iranian banks launder millions of dollars. The negative attention has some calling for better regulations, or even an end to the program.

Nevertheless, the money St. Kitts has made from the program has spurred other countries – from Malta to Bulgaria – to start their own. In the Caribbean, Antigua and Barbuda, Dominica, and Grenada have followed St. Kitts’ lead, and others are considering similar programs.

Citing economic headwinds such as lower tourism and high energy prices, St. Lucia Prime Minister Kenny Anthony said last month that he was open to the idea. “I think we cannot close our eyes [to selling citizenship] because it’s an option we may have to consider.”

Easy travel

Countries that offer economic citizenship do not release the number of applicants or approval rates. Nuri Katz, president of APEX Capital Group, a consultancy, estimates that between 15,000 and 20,000 people apply annually for second passports.

Pushed by political turmoil, or seeking a passport that requires fewer travel visas, applicants come from around the world, especially Russia, the Middle East, and Asia. A passport from St. Kitts offers visa-free travel to more than 120 countries.

“It’s all about the passport. 100 percent. Few, if any, of the people who want to apply are planning on living in those countries,” says Moscow-based Oleg Lemeshko, owner of Elma Global, which helps Russians obtain economic citizenship. “Most of the clients simply wish to have the ability to travel visa free.”

Dwyer Astaphan, a former St. Kitts minister of national security who now works as a citizenship lawyer, estimates the program generates tens of millions of dollars for the country, but concedes that “we don’t know where the money goes.” Still, the investment “is an economic vitamin b-12 shot for a country our size.”

Risky business?

A surge of new countries offering such programs has raised concerns over abuses. Earlier this year Malta raised eyebrows by hiring a private British company to screen new applicants, a role normally reserved for government. Malta has vowed to closely regulate the work of Henley & Partners.

“This is an industry that very few people understand, including governments,” says Mr. Katz, who is working to create a self-governing body for the industry.

On Tuesday, the US Treasury’s Financial Crimes Enforcement Network office advised international financial institutions to more closely review dealings with clients using a St. Kitts passport, the Wall Street Journal reports.

“We are evaluating what, if any changes should be made to our global program,” Prime Minister Douglas said at a press briefing.

Astaphan says he fears such scandals “are hurting the country’s reputation and that eventually European countries will say ‘we have to review these visa agreements.’

“And that will ruin it.”