In this paper I review previous analyses of specific indefinites, and propose a new analysis. The main claim is that a specific indefinite presupposes that an agent, a speaker in general, has in mind an individual which satisfies the descriptive content. I provide evidence for the ambiguity view of specificity. First, I show that a specific indefinite triggers a pre- supposition. Second, I show that a specific indefinite is a strong quantifier while a nonspecific is a weak one. Finally, I discuss different behaviors of specific and nonspecific indefinites in anaphora.