We prove a general mirror duality theorem for a subalgebra U of a simple vertex operator algebra A and its coset V = ComA(U ), under the assumption that A is a semisimple U ⊗ V -module. More specifically, we assume that A ∼ = i∈I Ui ⊗ Vi as a U ⊗ V -module, where the U -modules Ui are simple and distinct and are objects of a semisimple braided ribbon category of U -modules, and the V -modules Vi are semisimple and contained in a (not necessarily rigid) braided tensor category of V -modules. We also assume that U and V form a dual pair in A, so that U is the coset ComA(V ). Under these conditions, we show that there is a braid-reversing tensor equivalence τ : UA → VA, where UA is the semisimple category of U -modules with simple objects Ui, i ∈ I, and VA is the category of V -modules whose objects are finite direct sums of the Vi. In particular, the V -modules Vi are simple and distinct, and VA is a rigid tensor category.