The introduction of new and improved materials into silicon based integrated circuits is a major contributor in the recent decade to enable the scaling of circuit density and performance in analog, logic, and memory devices. Many new materials, such as complex metal oxides, magnetic materials and phase change materials, are much harder to pattern, thus pose significant challenges to the design and selection of plasma etching chemistries. This talk focuses on understanding the plasma-surface interaction and reaction kinetics, offers an unique approach in that thermodynamics analysis guides the selection of gas-phase chemistry, and establishes a kinetics-based model containing salient attributes of the etch process. The significant gain deriving from this unique approach is the ability to assess a large array of materials, which possess different properties that dictates a careful balance between etch anisotropy and selectivity. Both theoretical and experimental results from recent research will be discussed using complex metal oxides and magnetic materials are model systems.