MHARNESS models can contain multiple conductors, multiple shields, and multiple branches to capture the actual cable routing of real buildings, vehicles, aircraft, and spacecraft. Each branch segment can contain multiple layers of shields, wires and conductors – all immersed in a variety of respective media. Within MHARNESS are algorithms to analyze electromagnetic coupling through various cable shields to the conductors and wires within. Cable connectors, often possessing different impedence characteristics than the cable itself, are easily defined and employed. A variety of methods are available to terminate each conductor, wire, and shield within a cable harness including circuit termination. Many types of sources are available to drive the cable system including pin voltages, electric fields, current sources, and plane wave sources. MHARNESS can co-simulate within EMA3D for a multi-fidelity simulation of a large platform with fine detail in the harness. MHARNESS includes measured cable properties, such as diameters and transfer impedance. MHARNESS has a detailed GUI that makes it possible to quickly include all the information from a large cable harness into the 3D simulation.