Publisher Summary Epoxies are formulated from a wide variety of resins and hardeners that result in extremely specialized products for different purposes and applications. Today, epoxies have achieved a respectable status and are the accepted standard in machinery installation. Epoxy grouts are usually composed of three components: the resin, normally called Part A; the curing agent, or hardener, often called Part B; and the aggregate system. The epoxy molecule itself reacts again and again, growing in size, in a process called polymerization. This process of polymerizing and interlinking with surrounding molecules that are also polymerizing leads to the strong epoxy structure. Some of the most important factors influencing the rate of hardening, other than formulation, are the temperature of the substrate, the air temperature, and the temperature obtained by the mixed epoxy. The degree and type of chemical resistance is related to the specific epoxy formulation and the choice of curing agent. Over the years epoxy grouting technology has made tremendous advances. The grouting products of today are more crack-resistant and generate a lower exotherm than their predecessors did. Unfortunately, with all these technological advances, most grouting specifications have not been modified or corrected to reflect these changes. The one item that has been most affected is grout flow versus clearance.