Lignin, a structurally complex polymer within lignocellulosic biomass, presents a promising, sustainable pathway for producing high-value biochemicals. Traditionally a byproduct in pulp and paper industries, lignin’s rich aromatic structure, allows its transformation into diverse applications like biofuels, bioplastics, fine chemicals, and pharmaceuticals. This chapter focuses on the leading-edge lignin valorization processes such as its targeted fractionation, catalytic depolymerization, and thermochemical and biochemical conversions which enhance interfacing precision with effective transformations. The process of “lignin-first” fractionation largely facilitates maximizing the amount of pure lignin extracted while simultaneously maintaining its noncondensed structure to target a higher yield biochemical. Several breakthroughs in conversion efficiency and environmental impact have been made by oxidative and reductive cleavage techniques including novel catalyst and solvent systems. Lignin-based products find applications in biofuels, vanillin, phenolic compounds, and carbon fibers contributing to circular economy and reduction of fossil fuels.