The aim of this dissertation is to develop an integration theory against the Euler-Poincaré characteristic. Several families of topological spaces and definitions of the Euler characteristic for them are introduced, mainly a combinatorial and a (co)homological definition. Integration against Euler-Poincaré characteristic is defined and several properties are discussed. Finally, applications of the theory previously exposed are studied, both in the context of target enumeration in sensor networks and in Geometry and Topology. Particularly, alternative proofs of the Riemann-Hurwitz formula and of the characteristic of a fiber bundle are presented. Furthermore, it is introduced a generalization of the class of&n