Fermentation is well recognised as one of the food preservation techniques since human civilization.This biological driven process enhances many fermented foods with excellent nutritional values at reasonable price.Fermented food even serves as pool to obtain beneficial microflora for functional purposes. This well-illustrated text begins with the brief introduction on food fermentation and microbial interaction involve in fermentation.It also disclosures the beneficial bacteria and their potential functions that obtained from fermented foods.The detail description on fish sauce fermentation and preparation are included. The book also discussed in detail the microbiological dynamics involved in indigenous fish sauce fermentation of Malaysia and the characterization of beneficial microorganisms for their beneficial and technological properties. This book is all-in-one reference for researchers,professionals and students who has an interest to learn more about food fermentation andthe actual microbial interation involve throughout the process.