This book addresses key topics related to the broad subject of “Environmental Chemistry”. The book tries to present the topics that are essential to understand the chemical process in our environment—involving air,, water, and soil. Chapters that are very much current such as environmental nuclear chemistry, analytical tools needed for chemical aspect of our environment, solid waste and management methodology, quality criteria for air and water have all been treated in a simple fashion so that a reader can refer to advanced books in specific topics for better understanding. A brief review of fundamentals of chemistry is also included. References are listed that are easily available in the subcontinent and also many commonly accessed websites are also mentioned for better and detailed information on specific topics or sub-topics. The book follows the syllabus for “Environmental Chemistry” by UGC for M.Sc. as ell as by AICTE for M.Tech/B.Tech students in environmental engineering. The contents can be covered either in one semester course or in an annual mode with spread out teaching. Topics mentioned in this book can also form independent modules.