Abstract
This paper demonstrates the empirical application of Six Sigma to decrease the total number of delayed jobs (NODJ) in a service contracting company. The study is based on process information and primary data from a real project. DMAIC technique was used in this study to improve the service quality by investigating defects, defining the root causes and providing a solution to minimize the defect. The investigation shows that the mode of receiving jobs order and analyzing the requirements of the job influence the NODJ