Book excerpt: Biostimulants in Alleviation of Metal Toxicity in Plants: Emerging Trends and Opportunities focuses on the role of substances or micro-organisms whose presence can address issues of metal contamination in soils, seeds and plants. Including a range of biostimulant tools, the book highlights both endogenous and exogenous application. Written and edited by a global team of experts, this book presents an overview on biostimulants in determining metal toxicity. As plants encounter a wide range of environmental challenges during their lifecycle, among which metal toxicity is a common form of abiotic stress, this book thoroughly covers important topics on the subject matter. Once inside a plant system, toxic metals may initiate a variety of physiological alterations in plants, including adversely impacted seed germination, root and shoot growth, chloroplasts ultrastructure and photosynthesis, nutrients assimilation, carbohydrates metabolism, and plant hormonal status which, collectively, results in reduced plants yields. In addition to several naturally occurring physiological and metabolic re-programing responses, plants may also modify their root and shoot systems in order to dilute entered amount of toxic metals. As an additional tool biostimulants have emerged as one of the important plant protectors under adverse conditions. - Includes endogenous and exogenous application of biostimulants - Focuses on use based on specific metal contamination - Presents forward-looking prospects for the use of biostimulants in plant health protection