Ocimum: An Overview highlights the major milestones in the last three decades of taxonomical identification of Ocimum, providing insight into its potentialities and present demands. The authors explore the utilization of in vitro plant tissue cultures and genetic transformation systems for the improvement of sweet basil. An overview of the primary phenolic compounds found within basil is provided, along with their associated health benefits, and various strategies used to increase phytochemical levels in basil are discussed. Traditional uses of basil are discussed, including in the treatment of head colds and as a cure for warts and worms, as well as an appetite stimulant, carminative, and diuretic. The leishmanicidal and antimicrobial properties of Ocimum are discussed in an effort to assess its potential utility in the production of antimicrobials and leishmanicidal agents of natural origin. In closing, the authors summarize the main data on the biologically active substances and therapeutic activities of Ocimum species based on the current evidence.