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becoming a necessity for survival and not a practice to do.

Cost Evaluation: Why, what and how?

Many authors agree that 70-80% of a product cost is committed during the concept phase [Stewart et al. 1995; NASA 2002a; Taylor 1997; Mileham et al. 1993]. Making a wrong decision at this stage is extremely costly further down the development process. Product modifications and process alterations are more expensive the later they occur in the development cycle. Thus, cost estimators need to approximate the true cost of producing a product, based on empirical data, with the purpose of satisfying both the customer and company. In traditional costing there are two main estimates: a first sight estimate, which is done early in the cost stage, and a detailed estimate, done to calculate costs precisely. The former of these cost-estimating methods is largely based around the experience of the estimator. For example, it is not uncommon for a first sight project estimate to be based upon a past similar project or purely on experience in costing. However, to attain this level of experience takes years of apprenticeship and considerable oversight from senior estimators. Although useful for a rough order of magnitude estimate, this type of estimating is too subjective in today? cost conscious culture and more quantified and justified estimates are required [Roy et al. 1999a, 1999b]. For detailed estimates, cost is based upon the number of operations, time per operation, labour cost, material cost and overhead costs in case of hardware cost estimating. Much of the information in a detailed estimate is based upon the internal synthetics (times or costs based upon expected rates of work for any particular task) of the company. To generate these estimates, it is necessary to have an understanding of the product, the methods of manufacture/process and relationships between processes.

Detailed estimating goes through several iterations, since feedback from the relevant departments enables the estimates to be reviewed and improved. Thus, detailed estimating can be achieved only when a product is well defined and understood. Activity based costing (ABC) is a process for measuring the cost of the activities of an organisation [Dean 2003; Cokins 1998]. It is a quantitative technique used to measure the cost and performance of activities e.g. inspection, production processes and administration. Each activity within an organisation is first identified and then an average cost is associated. Once this is achieved, it is then possible to estimate the amount of activity a product is likely to need and then associate the relative costs. This makes ABC appealing since it combines estimates with hard data. This method follows similar processes to detailed estimating and also requires a detailed understanding of the product definition.

Cost control assessment of risk

The objective of a cost risk analysis is to predict the amount of uncertainties involved in the cost estimate of future projects. There will always be uncertainties, i.e. risks, involved in a project. If these uncertainties can be identified and quantified, effort can be made to successfully deal with the impact of them occurring. Risk management is a very broad term, meaning the management of any situation, which is controlled in one way or another by uncertainty. The aim of risk management is to minimise the negative impact of risk in