Abstract This article analyzes the factors determining the use of dedicated reflexives in natural language. It addresses the very diverse ways in which reflexivity is expressed and shows how to find the unity in this diversity. It takes as a starting point the fact that natural languages avoid expressions of the type Subject Verb Pronominal where the subject binds the object (and cases of co-argument binding in general) and then addresses the question of why this would be so. One factor concerns properties of predicates. A second factor concerns the syntactic representation of dependences between arguments. The article puts these factors into a general perspective and surveys a number of puzzling cases, such as languages with apparently locally bound pronominals. It then shows how superficially similar expressions may actually have rather different structures, putting them outside the scope of the factors discussed. Thus the observed diversity in fact reflects uniform principles.