The need for more food to sustain the growing human population has led to the conversion of forests to croplands. Excessive input of chemical fertilizers has exerted pressure on soil resulting in the deterioration of its quality and productive potential. The changing environmental conditions and climatic transformations have also adversely affected the properties of soil. Realizing the negative effects of chemical fertilizers on soil quality, various organic substances, waste materials and other substances were explored for their potential to be used as soil supplements. This book provides detailed information about various inorganic, organic, biological and other non-conventional soil supplements with emphasis to the role they play in maintaining soil fertility and increasing agricultural productivity. The soil supplements contribute a lot in restoring the productive potential of soil to a great extent. Each soil supplement possesses certain advantages and limitations in restoring the fertility of soil. Integrated fertilizer treatment proves beneficial in restoring soil fertility for various types of soils. The book provides latest information on the topic and describes advances in soil science.