Crohns Disease (CD) is one of the most important chronic inflammatory bowel diseases (IBD) that can affect the whole gastrointestinal tract from mouth to anus and whose inflammation extends through all layers of the gut wall. Treatments normally consist of controlling the symptoms, maintaining remission, and preventing relapse. Despite many years of study, the exact aetiology and pathogenesis of this disorder still remains unclear; however, great advances have been made in the last decades and have provided insights into the complex, multi-factorial processes and mechanisms that can result in chronic intestinal inflammation such as those present in Crohn's Disease. This book will describe etiological factors (host-microbiome interactions, nutrition, immune system, genetic and life-styles), novel and conventional diagnostic tools (magnetic resonance enterography, multidetector contrast-enhanced computed tomography, small bowel magnetic resonance imaging, intestinal ultrasound, endoscopy and histology), complications (musculo-skeletal, and intra-abdominal) along with conventional and novel treatment options (strictureplasty techniques, use of biological agents, probiotic micro-organisms and genetically engineered lactic acid bacteria) for CD and other IBD. This new book is a compilation of topics that have been written by experts from all over the world (Argentina, Australia, Brazil, Chile, France, Hungary, Italy, Spain, United Kingdom and the United States of America) who work in medical, clinical or research settings offering different viewpoints on the most up-to-date information currently available on Crohns Disease.