Formerly, additives were only used to inhibit the formation of solid hydrates in pipelines and maintain a safe and economic fuel transportation. Recently, their role has reversed in newly found applications, where formation of gas hydrates is beneficial like, gas storage and carbon sequestration. A comprehensive review on the role of conventional and novel additives used to promote or inhibit the hydrate formation in different chemical processes is presented. These additives are classified based on their action mechanism i.e. thermodynamic and kinetic. The study aims to provide a complete outlook of chronological development with a special focus on the major issues, challenges, and future prospects/development of the different classes of additives in a promoter/inhibitor role.