Abstract: This invention is a look-ahead method for determining optimum production schedules for each production step based on factory-wide monitoring of in-process part queues at all potential production bottlenecks. For each product having associated therewith a throughput bottleneck, a maximum queue quantity Q.sub.MAX and a minimum queue Q.sub.MIN quantity are assigned. When a machine completes a lot of a particular product at a production step P that proceeds the bottleneck step B, the look-ahead method is initiated. The queue at step P is searched and the next lot to be processed is selected. If that lot is a product for which Q.sub.MAX and Q.sub.MIN values have been assigned at step B, then the queue quantity at step B is determined. If, on one hand, the queue quantity at step B is less than Q.sub.MAX, or between Q.sub.MAX and Q.sub.MIN and the queue quantity is climbing upward from a sub-Q.sub.MIN value and has not yet exceeded its Q.sub.MAX value, then the lot is processed without further analysis.