The three clinical types of childhood diarrhoea include - acute watery, persistent and dysentery. Acute watery diarrhoea which lasts for less than 14 days constitutes 60 to 80% of childhood diarrhoea while persistent diarrhoea lasting for over 14 days forms 3 to 12% of all cases. The presence of blood in diarrhoea stool makes it dysenteric and this occurs in 10 to 20% of cases in the developing world. Childhood diarrhoea may be secretory, osmotic or invasive. Most cases of childhood diarrhoea in the developing world are infective. Close to 90% of enteropathogens in childhood diarrhoea are identifiable particularly with serology. This book discusses the aetiologies of childhood diarrhoea, as well as variance of these symptoms in different locations around the world.