The chemical and petrochemical industries consume nearly 30% of global energy use, nearly half of which is a result of chemical separations. A major opportunity exists in identifying more efficient, productive, and environmentally friendly processes that operate in a continuous fashion. One attractive possibility is membrane-based separations, but significant materials limitations exist in designing membranes that can selectively distinguish between molecules with sub-angstrom differences in size and nearly identical thermodynamic properties. This presentation will focus on several design strategies for leveraging functional microporous materials to control separation performance. A particular emphasis will be placed on new materials chemistries with a focus on testing materials under complex gas mixtures and for extended periods of time.