Every day many people suffer from intestinal diseases. These disorders can result from pathogens like bacteria, fungi, parasites and viruses, but the causes of non-infectious intestinal disorders and colorectal cancers remain to be elucidated. Disturbances to the normal gut flora (the microbiota) are central to the development of many, if not all, of these disorders.   Disturbed gut microbiota is a prelude to public health issues like traveller-, antibiotic- and Clostridium difficile-associated diarrhoea, irritable bowel syndrome, inflammatory bowel disease, and colorectal cancers.  This book discusses the way intestinal disorders affect the microbiota, how the disturbed microbiotal balance leads to enteric disorders and the ways to prevent these disorders. Further his book explores the potential of probiotics (live microorganisms that when ingested bring a health benefit) in treating enteric disorders by analysing the probiotic genome through proteomics, metabolomics and functional assays. Discussed is how the ingestion of specific microorganisms repairs the disturbed microbiota and subsequently ameliorates enteric disorders. Finally this book addresses how genetic engineering and biotechnology will contribute to the development of effective and safe designer probiotics.