Microbial bioprocessing has evolved from the use of undefined natural consortia to the construction of synthetic communities tailored to specific processes and bioproducts. This evolution is enabled by recent advances in biotechnology, including cultivation of non-model microbes, metabolic engineering, bioinformatics, and numerical modeling. Equipped with these powerful tools, engineers have designed co-cultures and consortia with an expanded set of capabilities, mainly via ‘bottom-up’ approaches that tether isolates together in culture. Here, we present a brief review of the opportunities, challenges, and recent developments in consortia-based bioprocessing with a focus on lignocellulosic biomass conversion. With improved understanding of microbial community composition and function, we further present a vision to harness defined consortia down-selected from nature via ‘top down’ approaches.