This chapter discusses the role of enzymes as biocatalysts in various technical applications, as well as the particular potentials of extremozymes and the biotechnological production thereof. Enzymes play a crucial role in biochemistry by lowering the activation energy of chemical reactions, thus enabling metabolism. In the food, pharma, and textile industry, for detergent production as well as bioenergy applications, technical enzymes find wide application. In particular, extremophilic organisms and their enzymes open up new perspectives for technical applications of these biocatalysts under non-standard conditions. Research in this realm contributes to the development of robust enzymes that perform adequately in desired non-physiological environments. The biotechnological production of vitamins, especially B-vitamins and vitamin C, which are water-soluble, is also discussed.