A great deal of attention has been devoted in recent discussions to the complementary (or nearly complementary) distribution of reflexive and non-reflexive pronouns within certain "local' domains in languages like English. As is well known, within such domains, non-reflexive pronouns must in some sense not corefer with one another, while reflexives have to have an antecedent. This phenomenon has been called "opacity' and in what follows we shall refer to it with the term "anaphoric opacity' (A-opacity for short) to distinguish it from what logicians call opacity. A-opacity is interesting not only in its own right, but also because of the role it plays in determining what kind of structural considerations are relevant in characterizing admissible types of binding in natural language.