The Common Agricultural Policy (CAP) of the European Union (EU) has been highly
political and social controversy, within the EU as well as at international level. However, the reforms on
the institutional structure have not been frequently analysed. This paper, based on the Institutional
Innovation Theory, examines the role of different exogenous and endogenous factors which have been
boosted or slowed down, the five CAP reforms. According to these factors we analyse three key issues
in the EU general political system, two topics in the EU domestic-economic system and the external
pressures. Later, these factors are considered on a theoretical approach applying investment theory and
expected utility maximization by means of the net present value model and dependency relations. The
main results show that role played by the EU institutional structure is fundamental as a limited factor,
and the external pressures and citizen’s acceptance of this policy are an important boost factor.
Keywords: Institutional innovation, common agricultural policy, political structures, allocation of public
funds, social changes.