The impact of biomarkers in present day health care system, health management and healthy life is enormous. Clinicians need them for diagnosis, prognosis, effect of therapeutic intervention, and most importantly, for early detection of a disease. Pharmaceutical industries need them for new drug discovery and drug efficiency test. Regulatory authorities need them for testing toxicity and environmental impact. Epidemiologists need them for population screening and risk factor determination. In post genomic era biomarkers would have a huge impact in personalized medicine and personalized health management. This scope of this book is not limited to just a few of the most important aspects of biomarkers but covers wide variety of subjects, from biomarkers cancer to neurodegenerative diseases. Chapters cover variety of aspects, from modern cell based technologies to molecular imaging; from drug discovery to critical care prognosis. A great amount of information is also devoted to bioinformatics and statistics. There is an enormous potential for commercial value of biomarkers. The global diagnostic market accounts for only 1-2% of government healthcare expense, however, it influences on 60-70% decisions in healthcare. My sincere thanks go to all the contributors of this book who took the extra effort beyond their busy schedules. Last, but not least I would like to express my gratitude to the publishing group for their tireless support