Solid oxide electrochemical cells (SOECs) typically operate at temperatures above 650˚C and can either produce electricity (as a fuel cell) or reduce carbon dioxide and water (as an electrolysis cell). SOECs are comprised of heterogeneous materials having spatially varying architectures exposed to strong oxidizing and/or reducing environments. Under these conditions, identifying where charge transfer occurs, measuring reversible (and irreversible) changes in SOEC material properties, and quantifying the kinetics of elementary steps in proposed reaction models present significant challenges. This workshop will draw leading investigators from a diverse collections of fields including chemistry, physics, materials science and engineering to discuss recent experimental and theoretical advances in the field of high temperature energy conversion with a particular emphasis on fundamental questions that limit the development of models capable of predicting microscopic mechanisms responsible for chemical oxidation and reduction in SOECs.