Many small states can sell a portion of their sovereignty. That's what offshore finance , offshore gambling, contributions for voting a certain way at the UN (China-Taiwan), are. Very lucrative. This probably explains a majority (not all) of the "successes". On average small states get large aid per capita because of lumpiness. Some small states have very good governance. Bill Easterly wrote a paper on small states growing faster than large countries, called "Small States: Small Problems?" Maybe this has more answers .