The Harding Loevner Frontier Emerging Markets Portfolio invests in smaller emerging markets and frontier markets, and is widely diversified across regions and countries.
Going frontier means adding lesser correlated assets to your portfolio, as the MSCI Frontier Markets Index shows 0.64 correlation to the developed markets and only 0.59 to the larger emerging markets in the EEM, according to Jackass Investing.
Markowitz built a diversified portfolio model that assumed that the portfolio structure would be located on the frontier point that would yield maximum utility.