S&C presented its paper, “Simulation of Bidirectional Flows in a Complex Pipeline Network” at Pipeline Simulation Interest Group in May. The paper shows how S&C tackles the challenges that arise when a project requires simulating an entire network, especially when this network contains looping, interconnections, and circular routes. The most significant simulation challenge is determining flow direction and dynamically simulating flow reversing within pipeline segments. System complexity creates difficulties predicting the system’s reaction to a regime change. A single change in one of the inputs initiates changes throughout the whole system and can reverse flow in pipeline looping and interconnections. This paper introduces a proposed simulation method to be used in such situations to calculate system dynamics and to model transient behavior of reversing flow.