This document provides information on the ancient Vedic practice of yagya (homa/havan/fire sacrifice) including its definition, importance, benefits, and historical significance according to Vedic scriptures. It discusses yagya from scientific, social, and subtle perspectives and provides case studies showing positive impacts on the environment, health, agriculture, and disasters. International organizations propagating yagya and contacts are listed. The conclusion is that yagya is a comprehensive solution to problems according to the Vedas and should be spread worldwide to help the environment and humanity.