The customers of the defence industry in South Africa are mainly overseas. Only 20% of Denel's turnover is due to local customers (South African National Defence Force). The defence industry in South Africa has to compete in the global world against harsh competition and in unfavourable conditions such as defence budget cuts and decline in need of defence products. Products must be of high quality and the latest technologies must be used in the products. Development time of products needs to be shorter because customers demand very quick response because they have a variety of suppliers to choose from. There is also a strong emphasis on life-cycle cost.

The research problem for this study can be summarised with this question: "How can processes be improved to adhere to the requirements of the customer in terms of schedule and quality?"

The objectives of this study are to define a method for continuous process improvement in order to:

• Meet the requirements of the customer in terms of specifications, price, schedule and quality
• Improve the rate at which the production process generates money through sales i.e. the throughput
• Increase cash flow and net profit of company.

The research project follows the practical implementation of a combined process improvement method on a production process. A combined process improvement method is defined by using a combination of Theory of Constraints (TOC) and Six Sigma. These two approaches were selected because TOC is used to focus the improvement process on the constraint within the process, whereas Six Sigma focuses on the variation within the processes in a system. Six Sigma methodology will be used to reduce the defects within a process. Continuous process improvement is of vital importance to all industry in the global market, as matured products need to be faster on the market. The products must be ready to be used operational. The environment of the customer must not be used as a development tool.

Keywords: Process, throughput, schedule, improvement, production.