The manufacturer's ability to respond quickly and with great flexibility is crucial. The future belongs to the manufacturer of high tech, high-value products who can compress not only component and assembly process times, but design and tooling cycles as well. Master production scheduling provides a road map for production requirements. This article reports the results of a simulation study that compares alternative procedures for determining master production scheduling (MPS) techniques utilizing the superbill and covering set MPS. The performance criterion for the study is the available-to-promise (ATP) lead time (customer service). The results of the simulation experiment support the superiority of the superbill technique over the covering set technique in terms of customer service. The penalty associated with using the more efficient covering set technique as an alternative to the well known superbill technique is a significant decline in customer service. However, covering sets have computational advantages that must be considered, especially when the MPS procedures have to be repeated routinely. Finally areas for future research are suggested. It is especially important that a trade-off between the customer service and manufacturing flexibility be investigated.