The use of analytical instrumentation is an exciting and fascinating part of chemical analysis that interacts with all the areas of chemistry and with many other fields of pure and applied science. Analysis of Martian soils, the body fluids of race horses, Olympic athletes and the engine oil of commercial and military jet aircrafts are examples of problems that require instrumental techniques.The book addresses the synthesis and characterization of hydrazones and their applications in the determination of metal ions by direct and derivative spectrophotometric methods. Applications of the developed spectrophotometric methods in real samples were also discussed. The book contains the literature survey of plethora of hydrazones used in determination of various metal ions.