The many uses of gluconic acid and some of its salts are arousing increasing interest in these compounds and in their production levels. Although gluconic acid and gluconates can be obtained chemically, they are currently almost exclusively biotechnologically produced, mostly by fungus based methods. There is, however, an ongoing search for alternative microorganisms to avoid the problems of using fungi for this purpose and to improve the productivity of the process. Especially promising in this respect are acetic acid bacteria, particularly Gluconobacter strains. This paper discusses the main variables and operating conditions to be considered in optimizing gluconic acid production by Gluconobacter.