Quantum inferentialism, as a metasemantics of standard QM, holds that the meaning of expressions in the language of the theory is determined by their inferential properties. This rejects the widespread view that meaning is determined by representational properties. After revisiting some conceptual background, two objections are formulated, from information-theoretic reconstructions and from extensions of Wigner’s friend scenario. Then the chapter focuses on the categoricity problem for quantum inferentialism. It also motivates the project of a non-inferentialist metasemantics for QBism, according to which meaning is determined by decision-theoretic properties.