The primary goal of this book is to enable effective, updated and easy preparation for UPSC and State PSC exams. Both the structure and content of the book have been carefully designed to serve the triple purposes of self-study, revision, and expert guidance to the aspirant. # Each chapter begins with Learning Outcomes, Chapter Analysis and Issues to Ponder to introduce the topics covered, develop curiosity, and capture student’s interest. # The book is filled with infographics at relevant places which is helpful to learn answer writing presentations of Mains exam writing. # The infographics or images are such that they can be memorized and elaborated in words for answer making. # Further, this is a Text-Guide in the sense that it combines the theoretical knowledge of a textbook with the practical, strategic aspects of a Guide. # This Text-Guide aims to solve all content and guidance-related problems of a student at once. # It is powered with a section called ‘Expert’s Advice’ where the author directly addresses, guides and instructs the student using his expert knowledge. # This will help the student to understand which sections are most important, what can be asked in future, and what should not be skipped strictly from exam point-of-view. # In terms of the content, the differences between Ecology and Environment and between Environmental Studies and Environmental Sciences have been clearly maintained throughout the book. # The writing style is lucid, concise and cross-referential. Sections from all chapters are linked with questions that previously appeared in Prelims and Mains, thus helping you keep the big picture in mind. # Prelims Confusing Terms Simplified, Prelims Pointers, Mains Pointers, Think Tank, and In short are mentioned throughout the book wherever necessary. # A separate Chapter with short revision notes encompassing the crux of the whole book, by the name of SNAPSHOT, is provided at the end of the Book. # This book is a comprehensive text-guide with exhaustive discussion in 45 Chapters. The theory is enriched with Previous year Prelims Questions, NCERT based MCQs and Mains related questions and answers. # There is detailed emphasis on concepts and anecdotes through factsheets in all the chapters.