In the case of human body, property of being strong and healthy is termed as robustness. If we consider in the case of system it may be termed as the talent of tolerating perturbations. For small changes the stability of the system is not affected. In the language of control system a control is said to robust if the system works well under the different set of assumptions. Hence robustness is analyzed by perturbation of the model parameters. This book highlights robustness analysis of a selected industrial delayed process in a systematic approach.