The flow of materials is a major constituent of in-plant logistics and the material handling system is a key factor in the performance of production/manufacturing system. Similar factors govern resource requirements and material flows. In particular, quality factors and the configuration of the quality assurance – the inspections' system. Nonetheless, only recently has the association between material flows, quality levels and the configuration of the inspections' system been noticed. Consequently, the dependencies of material flows on quality levels and the configuration of the inspections' system can be examined. The quality levels, the configuration of the inspections' system, and inspection error rates significantly affect the volumes of material flows. In addition, the configuration of the inspections' system affects the structure of the material flow network by adding nodes – inspection stations, to it and changing the flow paths, accordingly. These effects are demonstrated, examined and discussed in this talk.