What are the matter considered in order to establish federal structure in nepal​

Don’t bother with a federal system. Federations are more expensive from duplication of most agencies of government. And federations are much more complex and they just get even more complex with time. As complexity grows then the government becomes more prone to failures and problems of human error - nobody is smart enough to understand all the ramifications of even a simple policy initiative. Another troublesome feature of federalism is the diffusion of responsibility that can be supportive of corruption.

There’s a better alternative to federalism and that would be the adoption of a policy called subsidiarity. That is a principle that government power ought to reside at the lowest feasible level (i.e. at the local or regional level, instead of the national or supranational level, unless the latter presents clear advantages). Such a policy is not only wise and respectful of regional differences but is also flexible, adoptable and good for evolution according to the flow of history.

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