Globally, there is an increasing demand for minimally processed, easily prepared, and ready-to-eat fresh food, globalization of food trade, and distribution from centralized processing which pose major challenges for food safety and quality because perishable food may get contaminated with undesirable microorganisms. Food spoilage adversely affects the economy and also erodes the consumer's confidence. On other hand, food-borne illness leads to loss of earnings and productivity, unemployment and litigation, and weakens trade and tourism. Another challenge for the food producers is to produce less stable foods by processes that confer less harm to the detrimental microflora. A challenge for food producers is to develop products with a sufficiently longer shelf-life and at a competitive price. This brings them to the most promising approach to this end, the so-called biopreservation. This chapter provides a scientific background, functionality, as well as food applications and further commercial aspects of biopreservatives derived from microbial sources.