Aroma biotechnology opens access to natural volatile flavors. Due to the attribute of naturalness these aromas are the most valuable ingredients for foods, cosmetics and related products. The author describes biocatalyzed reactions and biogenetic routes leading to aroma and flavor compounds and he depicts in detail their utilisation in industrial scale processes. All the important topics, including de-novo-synthesis, genetic engineering, in vitro rDNA methods, laboratory requirements and techniques, upscaling, product recovery, profitability, and legal aspects are covered. R.G. Berger contributes his own experimental experience to all except one chapter and leads the reader into state-of-the-art aroma biotechnology.