People had a similar response when investors were dabbling in emerging markets during the '90s, Koesterich says. "Brazil and India - those used to be scary places, too."
Unlike the U.S. and Europe or even emerging markets like China and Brazil, frontier-market countries are a grab-bag group with little connection to each other. But they have a few things in common. They're small, growing quickly and some, like Kuwait and Qatar, are rich. Many of them shunned the outside world for years and are slowly opening their doors to outside investments.
Thanks to rapid economic growth, the MSCI Frontier Market index has gained 22 percent over the past 12 months. That compares with a 3 percent rise for MSCI's emerging market index, and 25 percent for the Standard & Poor's 500, the benchmark U.S. stock index.
Investing in frontier markets carries plenty of dangers. Argentina's government could decide to take over more private companies and leave investors with nothing. The war in Syria could spill into Lebanon and Jordan, upending their thriving markets. Ivory Coast, Pakistan and many of the 37 frontier countries have had coups, wars and other turmoil over the past two decades.
"Buying into them has to be a long-term play," says Jack Ablin, chief investment officer at BMO Private Bank. "You have to take some leaps of faith."
The steady rise of their stock markets has apparently helped investors put aside their worries. They've dropped money into frontier market funds week after week, raising the total to $3 billion so far this year, according to EPFR Global, a company which tracks the flow of investment funds. That's triple the amount deposited in them last year and just shy of the full-year record of $3.07 billion in 2010.
Cash has streamed in so quickly that Franklin Templeton's $1.3 billion frontier fund has decided to turn away new investors. Its top holdings include a Romanian oil and gas producer, OMV Petrom, and a batch of companies from Qatar and other countries on the Persian Gulf.
Last month, Wells Fargo's private banking group, which manages $170 billion in clients' money, took its first step into the frontier, pulling a portion of its money out of emerging-markets like Brazil, China and India and putting it into countries like Pakistan and Vietnam.