Purpose--The purpose of this paper is to test a method for improving decision-making at a tactical level--i.e. at the shop floor level. This is done by testing the use of the binary sorting algorithm (BSA) to improve decisions concerning quality improvement efforts among machine operators in a plastics manufacturer. Design/methodology/approach--The method used was the "action-research" approach since the researchers were actively involved in the training, implementation, and use of the BSA. Findings--It was found that using the BSA to prioritize quality improvement efforts by machine operators reduced the "scrap-from-line" rate in a plastics manufacturer. Research limitations/implications--The study should be replicated in different companies and industries using multiple methods because action-research is limited in its generalizability. Also, since the researchers are actively involved in the process, our observations could not be considered objective. Originality/value--To the authors' knowledge this is the first application of the BSA to improve decision-making at a tactical shop-floor level in a manufacturing company.