A reasonable functional definition would be that a GPG is "a good which it is rational, from the perspective of a group of nations collectively, to produce for universal consumption, and for which it is irrational to exclude an individual nation from consuming, irrespective of whether that nation contributes to its financing" [[3], page 9]. The main issue facing non-national (global or regional) public good provision is how to ensure collective action in the absence of a 'government' to directly finance and/or provide the public good, the response in the case of national public goods [4] .