The article reviews the use of water as a solvent in organic synthesis, highlighting its unique properties and advantages. Water, being the solvent of choice for natural processes, has been used in organic reactions since early studies, such as Wöhler's synthesis of urea and Baeyer and Drewsen's synthesis of indigo. Despite its potential benefits, water is not commonly used as a sole solvent due to the solubility requirements for reactivity. However, recent advancements have shown that reactions can proceed effectively in aqueous media, often with enhanced rates and selectivities. The review covers various organic transformations that benefit from being performed on water, including Diels-Alder reactions, 1,3-dipolar cycloadditions, Claisen rearrangements, multicomponent reactions (Passerini and Ugi), nucleophilic opening of three-membered rings, nucleophilic substitution reactions, and transformations catalyzed by transition metals. These reactions often exhibit improved efficiency and selectivity when performed in aqueous media, making them attractive for practical applications. Key examples include the accelerated Diels-Alder reaction of trans, trans-2,4-hexadienyl acetate and N-propylmaleimide on water, the efficient synthesis of cyanotriazoles from organic azides and 2-chloroacrylonitrile, and the CuAAC reaction of azides and alkynes in water. The review also discusses the use of water in metal-free carbon-carbon bond-forming processes, such as Wittig reactions and dehydrogenative coupling reactions. Overall, the article emphasizes the potential of aqueous organic synthesis for process intensification, environmental benefits, and the development of new synthetic methods.The article reviews the use of water as a solvent in organic synthesis, highlighting its unique properties and advantages. Water, being the solvent of choice for natural processes, has been used in organic reactions since early studies, such as Wöhler's synthesis of urea and Baeyer and Drewsen's synthesis of indigo. Despite its potential benefits, water is not commonly used as a sole solvent due to the solubility requirements for reactivity. However, recent advancements have shown that reactions can proceed effectively in aqueous media, often with enhanced rates and selectivities. The review covers various organic transformations that benefit from being performed on water, including Diels-Alder reactions, 1,3-dipolar cycloadditions, Claisen rearrangements, multicomponent reactions (Passerini and Ugi), nucleophilic opening of three-membered rings, nucleophilic substitution reactions, and transformations catalyzed by transition metals. These reactions often exhibit improved efficiency and selectivity when performed in aqueous media, making them attractive for practical applications. Key examples include the accelerated Diels-Alder reaction of trans, trans-2,4-hexadienyl acetate and N-propylmaleimide on water, the efficient synthesis of cyanotriazoles from organic azides and 2-chloroacrylonitrile, and the CuAAC reaction of azides and alkynes in water. The review also discusses the use of water in metal-free carbon-carbon bond-forming processes, such as Wittig reactions and dehydrogenative coupling reactions. Overall, the article emphasizes the potential of aqueous organic synthesis for process intensification, environmental benefits, and the development of new synthetic methods.