Geopolymers are networks of mineral molecules linked with covalent bonds. Geopolymers have a number of commercial applications and are used in medicine, high-temperature ceramics, and more. This volume includes four chapters discussing various aspects of geopolymers. Chapter One reviews some of the modifications, applications, and challenges of waste-derived geopolymer catalysts. Chapter Two investigates the adsorption of Cu(II), Mn(II), Pb(II), and Zn(II) ions to geopolymers obtained from biomass combustion ash. Chapter Three presents a summary of the literature on geopolymer concrete's foundations and disadvantages compared to portland cement concrete, mix proportions that give the best strength, management of fiber additives, performance analysis against burst rate, and resistance to attack. Lastly, Chapter Four deals with the development and application of sulfated geopolymer catalyst in the oxidation of dibenzothiophene.