This chapter presents three paradigms of IRS-aided WPCN to show the potential gain achieved by the IRS. In the first paradigm, we first study three special cases of the dynamic IRS beamforming, namely user-adaptive IRS beamforming, uplink (UL) adaptive IRS beamforming, and static IRS beamforming, and then a general optimization framework is proposed for dynamic IRS beamforming in half-duplex (HD) WPCN where any given number of IRS phase-shift vectors are available during one channel coherence. Moreover, we further extend the UL multi-use orthogonal multiple access (OMA) scheme to the NOMA scheme. In the second paradigm, we study the full-duplex (FD) system where the HAP is able to transmit signal and receive signal over the same frequency simultaneously and three IRS beamforming designs, are presented in FD-WCPN with linear EH model. In the third paradigm, we consider a more general case with the practical non-linear EH model and the multi-antenna system in the FD-WPCN, i.e, IRS-aided MIMO FD-WPCN. Several efficient optimization approaches are proposed to cater to different types of optimization problems. In addition, simulation results validate the theoretical findings, illustrate the practical significance of IRS with dynamic beamforming for spectral efficient WPCNs, and demonstrate the effectiveness of our proposed designs over various benchmark schemes.