Abiotic stresses have become a significant aspect of crop production, with their presence either in the soil, water, or atmosphere. The book aims to present the information regarding injury and tolerant mechanisms, variability for tolerance, breeding, and biotechnology for the improvement of crop plants against abiotic stresses in an organized manner, with up-to-date citations and a comprehensive literature of recent advances. The book emphasizes the elaboration of injury and tolerance mechanisms, as well as the development of improved genotypes against stress environments. The book also covers the plants symptoms of specific abiotic stress, reclamation of soil and crop/cropping patterns to overcome the effects of adverse conditions. Each topic is addressed with systematic approaches to develop abiotic stress-tolerant genotypes using biotechnological tools. The use of molecular markers in stress tolerance and the development of transgenic plants have also been detailed. Moreover, the book discusses the effects of air pollution and climate change on crop plants. It details the oxidative stress caused by abiotic stress, where plants produce a large quantity of free radicals (oxidants). The book is divided into seven major parts: physical stress (salt), water stresses (drought and waterlogging), temperature stresses (heat and cold), metal toxicities (aluminum, iron, cadmium, lead, nickel, chromium, copper, zinc, etc.), and non-metal toxicities (boron and arsenic), oxidative stress, and finally atmospheric stresses (air pollution, radiation, and climate change). This book will be beneficial for students and researchers, particularly Plant Breeders and Biotechnologists, as well as Botanists, to understand the injury and tolerance mechanisms and subsequently improve crop genotypes for abiotic stresses.