Parametric cost estimating, when properly used, is a powerful and cost effective technique. Unfortunately, it is often misunderstood and rejected by many potential users for whom it could be a beneficial tool. An agreement on how to use it and how to recognise its limitations is a major benefit to the cost estimating community. This book presents ways of parametrically forecasting costs and their advantages and disadvantages with examples from the mechanical, software and building industries; discusses most of the mathematical procedures useful for parametrically forecasting costs; introduces the judgement needed to audit the ways these techniques are used, firstly as a process and secondly as a tool to generate estimates. In Volume 1: The Parametric Approach: cost estimating is introduced; the preparation of data before utilization is discussed; the basic concepts of general cost estimating models are examined; the use of cost models is considered and finally, risk analysis is introduced.