Organic Agriculture or Organic Farming is the most widely recognised alternative farming system, which avoids or largely excludes the use of agrochemicals (synthetic fertilizers, pesticides, growth regulators, etc). It is gaining gradual momentum across the world, and growing awareness of health and environmental issues in agriculture although it was initiated before 10,000 years back in India when the farmers started cultivation depending on natural resources only. It is the production management system which promotes and enhances agro–ecosystem health, including biodiversity, biological cycles and soil biological activity. This is accomplished by using agronomic, biological and mechanical methods as opposed to using synthetic materials, to fulfill any specific function within the systems, which rely upon crop rotations, crop residues, animal and other different organic manures, legumes, green manures, vermiculture and vermicomposting, biogas slurry, on–farm and off – farm organic wastes, etc. controlling crop pests organically, maintaining soil health and sustain effort of supplying plant nutrients with profitable crop production. With this vision and mission keeping in mind, the book entitled “Relevance of Organic Farming” deals with Organic Farming including Organic Movement, concept, role, principles, relevance in present context, Status in India; Soils and Soil Environment for Plant Growth in Organic Farming, Humus Formation, Soil Health Card, Problems created by Modern Intensive Agriculture, Issues leading to Sustainable Agriculture; Status of Organic Farming, Global Scenario; Organic Farming in India; Organic Farming–Principle of Sustainability, Green Technology, Technologies for Producing Organic and Biofertilizers from Local Sources, Biological Technologies for Environmentally Safer Pest and Diseases Control, Organic Farming Systems, Crop Residue Management; Bio–Intensive Nutrient Management–Biofertilizers, Earthworms, Blue Green Algae (BGA), other Agronomic & Ecological Benefits, Vermiculture, Other Ecofriendly Farming Systems, Green Manuring, Neem for Organic Farming, Biogas Technology; Post Harvest Handling for Organic Crops, Research Activities on Organic Agriculture etc.