Industrial microbiology may be defined as the study of the large-scale and profit-motivated production of microorganisms or their products for direct use, or as inputs in the manufacture of other goods. There are many definitions of biotechnology. One of the broadest is the one given at the United Nations Conference on Biological Diversity (also called the Earth Summit) at the meeting held in Rio de Janeiro, Brazil in 1992. The conference defined biotechnology as “any technological application that uses biological systems, living organisms, or derivatives thereof, to make or modify products or processes for specific use.” This chapter introduces industrial microbiology and biotechnology and discusses the relationship between both fields, traditional biotechnology and modern biotechnology, the differences between the sub-disciplines of industrial microbiology and medical microbiology, multi-disciplinary nature of industrial microbiology, roles of an industrial microbiologist in the industry, patents and intellectual property rights in industrial microbiology and biotechnology, organizational set-up in an industrial microbiology establishment. It also presents the broad use of the terminology fermentation in industrial microbiology and biotechnology.