Policies that ensure that the currency is fully convertible, that it can be repatriated, and that sufficient foreign exchange will be available to allow investors to transfer profits out of the country, will help encourage private foreign investment. Currency convertibility can have significant impacts on investment as some project expenses, such as the cost of equipment, fuel and financing, can be in foreign currencies. The best practice is if there is both a law and a provision within the contract guaranteeing the ability of the investor to convert the currency, the availability of such currency, and the ability to repatriate it.