In complex endeavors, characterized by multiple interdependent participants with different functions and objectives, it is difficult for an entity to determine how to cooperate with other entities. Simply striving to cooperate at the highest level possible comes at high costs. But how should an entity determine what cooperation approach is appropriate? The present paper describes the newly developed LOCI-method (Levels of Chosen Interdependence) that can be used to determine ones position in the field of other participants, to map out existing dependencies, and to make choices about potential cooperation partners and cooperation approaches. It focuses on interdependence as the most important determinant and consequence of choices for cooperation partners and approaches. The method centers around the Interdependence Space, a three dimensional space with axes that correspond to three properties of interdependence: degree of dependence, mutuality of dependence, and degree of correspondence. An entity that employs the method fills the interdependence space with relevant parties according to their positions on the axes, by means of a questionnaire. Subsequently, the entity is guided in 'reading' the Interdependence Space to better understand the field of interdependencies. Finally, a set of generic principles facilitates in choosing the appropriate cooperation partners and cooperation approaches.