The book "Foundation of Agronomy" serves as a comprehensive resource tailored for students and aspirants preparing for a wide range of competitive agricultural examinations such as ICAR, ARS, NET, SRF, JRF, BHU, ARO, AAO, and Civil Services. It systematically covers core topics in agronomy, including agricultural meteorology, climate change, agroforestry, cropping systems, soil fertility, water science, and sustainable agriculture, among others. Emphasis is also placed on emerging domains such as precision agriculture and remote sensing. In addition to theoretical concepts, the book provides essential statistics and formulas to support exam readiness. This well-structured guide is designed to strengthen foundational knowledge and enhance problem-solving skills, making it an indispensable companion for those aiming to pursue academic excellence and careers in the agricultural sector.