  The Peccei-Quinn (PQ) solution to the strong $CP$ problem requires an
anomalous global $U(1)$ symmetry, the PQ symmetry. The origin of such a
convenient global symmetry is quite puzzling from the theoretical point of view
in many aspects. In this paper, we propose a simple prescription which provides
an origin of the PQ symmetry. There, the global $U(1)$ PQ symmetry is virtually
embedded in a gauged $U(1)$ PQ symmetry. Due to its simplicity, this mechanism
can be implemented in many conventional models with the PQ symmetry.
