Industry today is in a fight to survive. Competition is found not only on a domestic level, but also on international levels. In an effort to survive, all forms of production analysis, product reviews, and material reviews are made and periodically checked. Statistical process control is only one of the new methods used to reduce operational costs. However, one area many industries are now turning their attention toward is the maintenance function. Cost reduction in maintenance does not necessarily mean a reduction in service or in the quality of service. It means a better control of the maintenance organization and the related areas. In this part Isolation and Identification and their importance are discussed. These series of papers are taken from What Went Wrong a book written by Mr. Kletz.