This chapter introduces a two-layer network-constrained peer-to-peer (P2P) energy framework for multi-microgrids (MGs) systems. The framework aims to maintain the security of the distribution power network while enabling flexible energy trading between MGs. In the lower layer, MGs engage in energy trading through a P2P manner. The trading dynamics are emulated using a multi-leader multi-follower (MLMF) Stackelberg game model, while we prove the existence and uniqueness of the Stackelberg equilibrium (SE) and provide an explicit formula. A set of distributed algorithms is proposed to address privacy issues to determine the SE. In the upper layer, the distribution system operator (DSO) adjusts the network operation based on the outcomes of the P2P energy transactions, employing AC optimal power flow techniques and considering network reconfiguration. If network congestion arise, the DSO may request adjustments at the lower level to ensure network security. The DSO’s operational problem is reformulated into a mixed-integer second-order cone programming (MISOCP) model to ensure precision in solutions. Results from simulations of a 4-MG setup, as well as modified IEEE 33-bus and 123-bus distribution systems, illustrate the practical benefits of the proposed trading model and its solving method.