Sweet sorghum [Sorghum bicolor (L.) Moench] is a multipurpose crop (food, feed, fodder and fuel) that has the potential as an alternative biofuel feedstock without impacting food and fodder security. This chapter entitled ''Sweet sorghum: From theory to practice'' discusses on the historical developments in sweet sorghum and immense range of genetic variability that was available in major sorghum regions of the world. The candidate feedstock characteristic traits of sweet sorghum vis-a-vis other major biofuel feedstocks like sugarcane, corn and sugar beet were compared. Sweet sorghum fares well in many aspects as it is a C 4 species with greater resilience to diverse agro-ecologies, low fertilizer and water requirement besides short lifecycle. Hence, many consider it as climate change ready crop; some consider it as miracle crop and few term it as a smart crop. A quantitative insight into the production-ecological sustainability of sweet sorghum biofuel feedstock production systems has been discussed. The ongoing R&D efforts at ICRISAT as well as in National Agricultural Research System (NARS) on sweet sorghum value chain were highlighted. The breeding efforts in Brazil, USA and China on this crop are briefly narrated.