Ayurveda, Unani, Siddha and Homeopathy medicines are the major systems of indigenous medicines. Among these systems, Ayurveda is most trusted and widely practiced in India. Acorus calamus Roots and rhizomes have been used in Indian system of traditional medicine for hundreds of years and it is highly valued as a rejuvenator for the brain and nervous system and as a remedy for digestive disorders. In the present book we have discussed recently recognized many newer bioactivities and chemical composition of Acorus spp. This study would be very useful for those conducting researches on bioactivity screening in Acorus spp. and similar other less studied species of the plants. Acorus rhizome and its constituents, particularly a and b-asarone, possess a wide range of pharmacological activities such as antiulcer, cytoprotective, antispasmodic, hypolipidemic, anticonvulsant, antibacterial, analgesic, CNS depressant, insecticidal, antioxidant, memory enhancing, immunosuppressive, antidiarrheal activity and anticancer activities. It is also use in the treatment of cough, fever, bronchitis, depression and other mental disorders, tumors, hemorrhoids, skin diseases, numbness and general debility. They are also employed for kidney and liver troubles, rheumatism, sinusitis and eczema.