The paper introduces a new multi-channel integration method, called Single-Diagram-Enhanced multi-channel integration, and its implementation in the event generator MadEvent. This method automates the identification and integration of relevant subprocesses for a given process, generating both amplitudes and mappings for efficient phase space integration. The method is particularly useful for processes involving a large number of particles, such as multijet final states in association with leptons or missing energy, which are relevant for physics studies at present and future colliders. The authors demonstrate the effectiveness of their method through several examples, including vector boson production, heavy-quark pair production, and Higgs boson production, showing good agreement with other available codes. The paper also discusses the potential improvements and future developments in MadGraph to handle even more complex processes.The paper introduces a new multi-channel integration method, called Single-Diagram-Enhanced multi-channel integration, and its implementation in the event generator MadEvent. This method automates the identification and integration of relevant subprocesses for a given process, generating both amplitudes and mappings for efficient phase space integration. The method is particularly useful for processes involving a large number of particles, such as multijet final states in association with leptons or missing energy, which are relevant for physics studies at present and future colliders. The authors demonstrate the effectiveness of their method through several examples, including vector boson production, heavy-quark pair production, and Higgs boson production, showing good agreement with other available codes. The paper also discusses the potential improvements and future developments in MadGraph to handle even more complex processes.