The book provides an updated overview of molecular analysis of human tissues, and the impact this analysis has on diagnosis and prognosis of human diseases. Special emphasis is placed on human cancer and the future directions of the field. Methods of handling clinical tissue samples, including the impact of handling on subsequent molecular analysis, are also discussed. In addition, detailed protocols for molecular analysis of DNA, RNA and protein, with special emphasis on molecular analysis of highly complex human tissue samples containing mixtures of cell populations, are provided.