Lignin, a major component of lignocellulose, is the largest source of aromatic building blocks on the planet and has significant potential as a starting material for biobased products. Despite challenges in its structure, recent strategies have enabled efficient catalytic or biocatalytic depolymerization to produce defined aromatic monomers. This review summarizes novel approaches for lignin valorization, including catalytic strategies, functionalization, and defunctionalization, as well as the application of lignin-derived compounds in biobased polymers and pharmaceuticals. It highlights the importance of lignin fractionation, pretreatment, and catalytic methods to achieve high yields and selectivity. The review discusses various catalytic processes, such as oxidative and reductive depolymerization, and their impact on product yields. It also covers the potential of lignin-derived monomers in producing biobased polymers and pharmacologically active compounds. The review emphasizes the need for integrated biorefinery approaches to fully valorize lignocellulose components and highlights the role of catalytic methods in converting lignin to valuable chemicals and fuels. The review concludes with the potential of lignin-derived platform chemicals in future applications.Lignin, a major component of lignocellulose, is the largest source of aromatic building blocks on the planet and has significant potential as a starting material for biobased products. Despite challenges in its structure, recent strategies have enabled efficient catalytic or biocatalytic depolymerization to produce defined aromatic monomers. This review summarizes novel approaches for lignin valorization, including catalytic strategies, functionalization, and defunctionalization, as well as the application of lignin-derived compounds in biobased polymers and pharmaceuticals. It highlights the importance of lignin fractionation, pretreatment, and catalytic methods to achieve high yields and selectivity. The review discusses various catalytic processes, such as oxidative and reductive depolymerization, and their impact on product yields. It also covers the potential of lignin-derived monomers in producing biobased polymers and pharmacologically active compounds. The review emphasizes the need for integrated biorefinery approaches to fully valorize lignocellulose components and highlights the role of catalytic methods in converting lignin to valuable chemicals and fuels. The review concludes with the potential of lignin-derived platform chemicals in future applications.