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Lignin is the second most abundant biopolymer on earth and is a major source of aromatic compounds; however, it is vastly underutilized owing to its heterogeneous and recalcitrant nature. Microorganisms have evolved efficient mechanisms that overcome these challenges to depolymerize lignin and funnel complex mixtures of lignin-derived monomers to central metabolites. This review summarizes recent synthetic biology efforts to enhance lignin depolymerization and aromatic catabolism in bacterial and fungal hosts for the production of both natural and novel bioproducts. We also highlight difficulties in engineering complex phenotypes and discuss the outlook for the future of lignin biological valorization. A sustainable lignocellulosic bioeconomy will not be realized without overcoming hurdles associated with the structural complexity associated with lignin waste streams. Metabolic engineers capitalize on robust, naturally occurring funneling pathways that convert a wide spectrum of substrates to a few key intermediates for ring cleavage and conversion to central metabolites. Expanding the reaction conditions and the range of substrates for lignin depolymerization and funneling enzymes should improve lignin valorization by microorganisms. [ABSTRACT FROM AUTHOR]