Belize's official currency is the Belize dollar. For so many years, this has been pegged to the US dollar at around 2 to 1, though money changers in the underground market sometimes give a higher exchange rate of 2.2 to 1 or even higher depending on the local demand for the US currency.
The thing with the Belize dollar is that it is not that well-known outside of its borders. It is hardly exchangeable in any place outside the country, except for some border areas in its neighboring countries, perhaps. This puts the Belizean currency at a not-so-very-good position.
In the past, there has been some talk about adopting the US dollar as the official currency instead, similar to what El Salvador and Ecuador has done. Until this very day, however, there has not been much action dedicated to this pursuit yet. One of the major reasons seen here is the government's own reluctance to drop its Central Bank and lose its monetary policying powers to the United States. There is also this consensus among lawmakers that it is always easier to print money than to earn them during difficult times. Both reasons are, of course, valid and understandable.
Despite the Belize dollar's continued existence, the US dollar is still widely used, probably because of the high concentration of Americans in the area. It's just that it's possible to get a mix of Belize and US dollar bills as change for your money.
In this regard, I guess it's just right to say that it is important to keep a lot of your liquid assets in US dollars because they are relatively more stable in terms of purchasing power. It is also important that a large portion of this income is stored outside of the country just in case something awry happens in the country's economy.
There are also only five commercial banks in the country, offshore banks not included, making the banking sector somewhat uncompetitive.