During the past few years, pultrusion of thermoplastic composites has shown the promise of becoming a major new force in the pultrusion industry. Advantages of thermoplastic pultrusion are the improved toughness, higher service temperature, and post-process formability that these advanced composite systems offer over thermosetting systems. However, the pultrusion of thermoplastics is much different from that of thermo setting materials, and much work remains before the processing of these materials becomes as well understood as that for thermosetting materials. This paper will describe the results of an experimentally based statistical study to determine the critical process pa rameters of the pultrusion of a thermoplastic material and how those parameters interact to affect the quality, integrity, and cost of the pultruded components.