Abstract: David Sobel has recently argued that libertarian theories that accept full and strict self-ownership as foundational confront what he calls the conflation problem: if transgressing self-ownership is strictly and stringently forbidden, it is implied that the normative protection against one infringement (say, being stabbed) is precisely as strong as against any other infringement (say, touching someone’s hand without that person’s consent). But this seems to be an absurd consequence. In defense of libertarianism, I argue that the conflation problem can be handled in a way that allows us to honor basic libertarian commitments. It is suggested libertarianism should be characterized as presumptive libertarianism, treating self-ownership as an assumption the content of which remains to be worked out when applied, rather than as a dogma ready for application: a proposal that relies on a standard market model. Since such a proposal is likely to appear to many philosophers—libertarians in particular—as inherently flawed, a considerable part of this article defends it against possible criticisms. It is argued that presumptive libertarianism is not only a coherent and theoretically elegant notion, but a version of libertarianism that honors pre-theoretical commitments to self-ownership and liberty better than some mainstream versions of libertarianism.