This document describes the biology of Gossypium hirsutum (upland cotton) and Gossypium barbadense (pima cotton), with particular reference to the Australian environment, cultivation and use. Information included relates to the taxonomy and origins of cultivated G. hirsutum and G. barbadense, general descriptions of their morphology, reproductive biology, development, biochemistry, biotic and abiotic interactions. This document also addresses the potential for gene transfer to occur to closely related species. The purpose of this document is to provide baseline information about the parent organism in risk assessments of genetically modified G. hirsutum or G. barbadense that may be released into the Australian environment.