The complexity of specifications and the number of materials options available today for concrete production mean that the traditional procedure of making trial mixes is now unnecessary, expensive and time consuming. However the data generated by trail mixes can be incorporated into the development of computer-based systems and combined with knowledge generated through research and practice.J.D Dewar has spent much of the last 20 years developing systems by which a small amount of materials data can be used confidently to predict the composition of the ideal product to satisfy a specification with maximim economy, or to provide the "batch book" to fulfill all requirements using a specified combination of materials. Equally useful is the potential for forward control by the continuous adjustment of designs to take account of current or developing materials properties.