If the management of organizations, the fostering of public policies or the deployment of development (cooperation) projects follow one another in a practically deterministic way (if I do A, then B will happen) and a linearly way (few variables, always in a single direction), as environments grow in complexity, project management and impact public policies should also change. The Theory of Change identifies the necessary resources to carry out activities that will have expected results controllable to a certain extent; and, based on these results, and the causal relationships inferred or found by experimentation, expect to be able to influence directly to achieve effects and, indirectly, to achieve results, impacts.