This chapter provides a comprehensive overview of the diverse enzymatic strategies employed in pulp and paperPaper processing, emphasizing their growing role in sustainable and energy-efficient manufacturing. It highlights key classes of enzymesEnzymes—including xylanasesXylanase, laccasesLaccase, pectinasesPectinase, mannanasesMannanase, esterasesEsterases, and ligninLignin-degrading oxidoreductasesOxidoreductases—and explains their specific functions in biopulpingBiopulping, biobleachingBiobleaching, refiningRefining, sticky controlSticky control, and deinkingDeinking. The chapter underscores the advantages of enzymeEnzymes cocktailsEnzyme cocktails over single-enzyme systems, particularly their synergistic ability to enhance delignification, improve brightness, strengthen fiber properties, and reduce chemical consumption. Influencing factors such as pH, temperature, pulp type, and enzyme–substrate interactions are discussed to demonstrate the importance of process optimization. Collectively, the chapter presents enzymesEnzymes as essential tools for advancing greener, more efficient pulp and paper technologies.