The chemistry of the precursors used for producing alkali-activated cements plays a significant role in phase assemblage and evolution, and consequently the structure and durability of these materials.It has been identified that the MgO content of slag modifies the reaction kinetics and phase assemblage in alkali-activated binders.Based on this, the complex thermodynamic and chemical interactions occurring during alkali-activation of slag are likely modified by the presence of different contents of Mg in the system.The inability to control key compositional parameters due to the varying composition and mineralogy of commercial slags has made it difficult to determine the governing thermodynamic relationships and factors controlling reaction kinetics and phase assemblages from a more holistic perspective.