The Complex Interplay Between Gut–Brain, Gut–Liver, and Liver–Brain Axes provides current and wide-ranging information in the field of gastrointestinal, liver, and brain interactions that can be used in resolving important clinical issues. This book is systematically split into three distinct sections. The first section introduces the pathophysiology of the gut–brain connection, including the causative effect of the interactions between the gut and brain in gastrointestinal and psychiatric/neurological disorders, and the role of serotonin and its pathways in gastrointestinal disorders. The second section examines the pathophysiology of the gut–liver connection along with the interactions between gut microbiota and liver in chronic liver diseases, with special focus on the role of serotonin and its pathways in hepatic fibrogenesis. Finally, the third section describes the pathophysiology of the liver–brain connection, including the role of gut microbiota in hepatic encephalopathy, as well as dietary and therapeutic interventions that target the gut microbiome.