Holographic renormalization provides a framework that makes the AdS/CFT correspondence computationally precise. It systematically resolves the divergences and ambiguities that arise when relating bulk gravitational actions to boundary correlation functions. In this seminar, I will review how correlation functions of a conformal field theory can be extracted from gravitational dynamics in asymptotically AdS spacetimes using this method. I will explain how divergences of the on-shell bulk action near the AdS boundary reflect ultraviolet divergences in the dual field theory, and how these are removed by introducing covariant boundary counterterms. The resulting renormalized action generates well-defined one- and two-point functions, while bulk interactions are encoded in Witten diagrams that compute higher-point correlators.