Resumen
The trade of wheat and wool has been one of the economic pillars of the Kingdom of Naples during Modern Age. Since Romans times the production of these commodities in the continental part of the Kingdom has been regulated by the trashumance system that coordinated the flow of sheep on Puglias Tavoliere lands. We would highlight the role exercised by the institutions as development agents. In particular, the paper would demonstrate that the new institutions introduced by the king Alfonso I of Aragon were the main driver not only of trashumance but of the entire economic framework of the kingdom. A simple analytical model based on the complementary dynamics of pasturing and wheat production shows the results of the functioning of the new system. The results challenges the negative interpretation of the trashumance led on by the Neapolitan Reformers (illuministi) at the end of XVIII Century and widely absorbed by historians in the XX Century.