Most of the research carried out on olive oil has been concerned with its chemical and nutritional characteristics, whereas research focused on microbiological studies have been limited. Among the vegetable oils, olive oil is found to be an effective inducer for the production of lipases from various micro-organisms. The extraction of olive oil generates huge quantities of solid waste and dark liquid effluents. Though these wastes contain considerable amounts of valuable substances like sugars, oils, fibers and polyphenols, they are either wasted or used at low technological and economical levels. Moreover, the presence of polyphenols in the olive press cake inhibits the growth of micro-organisms. This book reviews research and discusses the various industrial applications which rely heavily on olive oil.