The third edition of this popular textbook covers the latest (April 2015) syllabus of the Ability Enhancement Compulsory Course on Environmental Studies, prescribed by the University Grants Commission (UGC) under the new Choice-based Credit System. It also includes additional topics included in the syllabi of some universities. The book is meant for undergraduates of all disciplines. Assuming very little background in mathematics or science, it gives a balanced presentation of the major issues and concerns related to the environment. This book will also be useful for those taking the UPSC civil services examinations, since it covers the ecology/environment topics of the preliminary and main examinations. The book discusses the major environmental problems we face today: runaway growth, imperilled ecosystems, disappearing forests, endangered species, dwindling natural resources, dangerous toxic wastes, green laws, and other such issues. It illustrates various problems, solutions, successes, and failures using more than 80 real-life case studies from India and elsewhere. Written in a student-friendly manner, the text is enriched with a large number of illustrations.