Intensive agriculture based on synthetic inputs popularly known as "Green Revolution" has practically replaced our traditional natural renewable resource based agriculture over last 40 years. Although, the initial results of this technology were very exciting and resulted into four fold increase in production but all this success has come on the cost of future generations and our environment. Biotechnological harvesting of microbial potential in nutrient mobilization and plant protection is one of the widely acclaimed options, which suits both the requirements of optimum production and environment sustainability. Use of microbial systems for nutrient mobilization, popularly known as biofertilizers are getting popular day by day and new and new systems are being introduced to meet our requirement of different crops and under different cropping systems. The book "Biotechnology in Sustainable and Organic Farming--Scope and Potential" is a compilation of chapters contributed by the eminent Indian scientists having considerable national and international reputation with many years of research, teaching and extension experience in the field. In these chapters an attempt has been made to give up-to-date information on various aspects of microbes and microbial systems being exploited for crop production. These articles include compilation of research on bacterial systematics, biology, biochemistry and biotechnology of plant-soil-microbe system. It also includes the present status of biofertilizer industry, it's statistics, problems and scope.