Gromov–Witten theory studies curve counting on smooth projective varieties through intersection theory on moduli spaces of stable maps. The Virasoro conjecture, proposed by Eguchi, Hori, and Xiong and extended by Katz, predicts a system of differential equations for the descendant Gromov–Witten potentials of smooth projective varieties. In this talk, I will first introduce the Virasoro conjecture and then discuss a construction of relative Virasoro operators for a smooth projective pair (X,D). Assuming the Virasoro conjecture for D, we establish the equivalence of absolute and relative constraints and prove compatibility with degeneration under a completeness condition. This is joint work with Shuai Guo and Lei You.