Rapid urbanization and industrialization have led to large amounts of aqueous effluents that, in many cases, contain toxic contaminants. Different physical and biological processes are used to remove pollutants from industrial wastewater prior to environmental discharge. Conventional treatment methods become more costly and less efficient for treating adsorptive pollutants such as heavy metals and ionic dyes. The advancement of biosorption as an alternative technology has been developed to overcome these drawbacks. Biosorption is a property that binds and accumulates metal ions from water solutions through inactive, non-living substances of biological origin that are known as biosorbents. In the selection of biosorbents, cost, quality, and availability are the main factors for large-scale industrial applications. Research is increasingly concerned with the use of natural materials for removing heavy metals. Native biosorbents can be generated from industrial wastes that are freely available: organisms that are accessible in large quantities and are cultivated specifically for the biosorption process. Biosorbents such as microorganisms (fungi, algae, and bacteria), plants (alive or dead), agricultural wastes (fruit/vegetable waste, rice straws, wheat bran), natural residues (sawdust, tree barks, weeds), and biopolymers (polysaccharides, chitosan, cellulose) have proved to be eco-efficient and possess strong biosorption properties for heavy metals and toxic pollutants. The easy availability and cost-effective processing of these biological sources into biosorbents have resulted in the maturity and broad prevalence of biosorption technology. This chapter provides an in-depth analysis of each group of biosorbents to examine the various factors that influence the process and the mechanisms on which they are centered. The chapter also provides future perspectives on biosorbents along with recent research. © 2023 Elsevier B.V., All rights reserved.