The main objective of this research is to minimize the defects of manufacturing process by investigating the factors resulting in bad quality and propose Optimal quality control and management solutions that are relevant to the production system of the design and manufacturing company, with the case study for the company ECE, a company in UK working in the area of design and manufacturing of handling and air-conditioning products. Different techniques were used to investigate the current and potential problems and risks related to design and manufacturing activities of the company, including the quality check sheets and survey as well as brainstorming and cause-effect method. The primary study results showed that implantation of check sheets and fishbone diagram for the typical design and manufacturing projects could reduce approximately at least 30 per cent of product defects in ECE.