Environmental contamination and climate change-induced abiotic stresses, such as high or low temperature, water logging or drought, high salinity, pesticides, heavy metals, and radiation like ultra-violet are detrimental to plant growth and development, leading to great loss in crop yield worldwide. It is getting essential to provide crops with multi-stress adaptation to alleviate the burden of environmental stresses and to fulfil the inevitability of population growth, as various abiotic stresses generally evolve simultaneously in the fields. To combat these environmental stresses, plants develop certain defence responses against abiotic stresses, including some biochemical and molecular aspects like reactive species scavengers, molecular chaperones, compatible solutes, plant growth regulators and antioxidative defence system inside cells. In response to stress, they are orchestrated by a composite regulatory complex involving signalling molecules like stress hormones, reactive oxygen species, polyamines, phytochromes, and calcium, as well as stress proteins. In this book, we aim at presenting the effects of different abiotic stresses on plants and an overview of various defensive systems and the regulatory network, along with their practical potential via some biotechnological tools like genetic engineering and/or exogenous applications, because understanding the abiotic stress response mechanisms in plants will help to improve the growth rate and productivity of crops. The book has 6 chapters which deal with the effect of different abiotic stresses in plants caused by environmental contamination and climate change and the remedial strategies. We believe that this book comprises a wealth of knowledge to botanists, agriculturists, students and researchers of colleges and universities.