A brief review of our current applications of the Embedded Atom Method (EAM) and Modified Embedded Atom Method (MEAM) is given in this paper as they relate to the structure of interfaces in materials. The EAM is used to consider the effect of hydrogen on the structure and properties of boundaries in nickel and nickel aluminide (Ni3Al). In both cases hydrogen segregates to the boundary causing a reduction in the cohesive strength. Next, the EAM is applied to describe the equilibrium and dynamic structure of a dissociated Σ3(112) boundary in copper. Comparison is made to recent experimental observations which show good agreement with the modeled behavior. Finally, the MEAM is used to help understand the properties of both the nickel/silicon and aluminum/sapphire systems.