Artemisinin, a sesquiterpene lactone originally extracted from the medicinal plant Artemisia annua L., is an effective antimalarial agent, particularly for multi-drug resistant and cerebral malaria. However, the concentration of artemisinin in the plant is very low. Because the chemical synthesis of artemisinin is complicated and not economically feasible in view of the poor yield of the drug, the intact plant remains the only viable source of artemisinin production. Therefore, it is necessary to increase the concentration of artemisinin in A. annua to reduce the cost of artemisinin based antimalarial drugs. Plant scientists have focused their efforts on A. annua for a higher artemisinin crop yield. With the present volume, we are bringing together the research which is being done on this plant throughout the world and future possibilities for scientists and researchers who want to work on it.