Sintering is a manufacturing technique that has existed for centuries to make bricks, china and pottery and is now increasingly used to produce a wide range of high-tech materials and products. Modern modeling techniques are now being employed to improve the efficiency of sintering and increase its usefulness in new technology applications. The structure of the book shows that sintering models are applied at three length scales: the atomistic-scale, the particle-scale and the component-scale. Sintering is then viewed as a multi-scale process and the mathematical techniques linking the models at the three scales are discussed. Powder compaction models are also outlined which provide the initial conditions for the sintering analysis. Two computer programs which can be used by researchers and practitioners to model sintering at the particle and the component scales are provided on the attached CD-ROM. Numerical examples are provided throughout and compared with experimental data where possible.