In the previous chapter we studied the usual protectionist measures – customs duties and quotas – which were specifically designed to protect a national activity from external competition. The protectionist effect is measured by the gap that is thereby introduced between, on the one hand, the relative price of two goods on the international market and, on the other hand, the relative price of these same goods on the domestic market. From this point of view, the protectionist intention does not matter much. As far as it causes a difference in relative prices between the inside and the outside, a measure of economic policy has a protectionist effect. The effects of such measures are the ones we have studied: changes in the structure of production, compulsory transfers, loss of well-being for some people.