Liberalism introduces ideas as a factor, additional to material interests, that must be taken into account in order to comprehend foreign policy. On the other hand, constructivism points out ideas as the main pillar upon which foreign policy is constructed, and whose understanding is the first fundamental step in order to explain the decisions made by actors in the international system. Peace Laboratories case, as the main European Union foreign policy instrument in Colombia, is taken here in order to illustrate de discussion.
