The Tenth International Conference on Molten Slags, Fluxes and Salts (MOLTEN16) was held in Seattle, Washington, USA from May 22-25,2016 and organized by TMS (The Minerals, Metals & Materials Society). The conference purpose was to provide an opportunity for scientists and engineers to share their new research findings, innovations, and industrial technological developments. The conference also aligns quite well with the TMS strategic goal to sustain and grow the core innovation in process engineering and to develop novel materials. The organizers are pleased to conclude that the set strategic goals were met and a very high-quality technical program with the participation of expert researchers in the field was held. The conference was focused on ferrous and non-ferrous metallurgy where ionic melts, slags, fluxes, or salts play important roles in industrial growth and economy worldwide. Technical topics included are: thermodynamic properties and phase diagrams and kinetics of slags, fluxes, and salts; physical properties of slags, fluxes, and salts; structural studies of slags; interfacial and process phenomena involving foaming, bubble formation, and drainage; slag recycling, refractory erosion/corrosion, and freeze linings; and recycling and utilization of metallurgical slags and models and their applications in process improvement and optimization. These topics are of interest for not only traditional ferrous and non-ferrous metal industrial processes but also for new and upcoming technologies.