A technique for improving readability of Forrester Diagram in system dynamics

We describe a three-pass algorithm for improving the readability of Forrester Diagram in system dynamics. The first pass converts Forrester Diagram to recurrent hierarchy. The second pass sorts the vertices on each level, with the goal of minimizing crossings. The third pass is a finite tuning of the layout that determines the horizontal positions of vertices. An illustrative example is given to verify the result.