The chapter discusses the role of glycosylation in health and disease, highlighting the glycome as the complete repertoire of glycoconjugates composed of carbohydrate chains (glycans) covalently linked to lipid or protein molecules. Glycoconjugate synthesis is a dynamic process influenced by enzymes, sugar precursors, organelle structures, and cellular signals. Studies of rare genetic disorders affecting glycosylation have emphasized the biological importance of the glycome, and technological advancements have improved understanding of its complexity. Changes in glycosylation can modulate inflammatory responses, viral immune escape, cancer cell metastasis, and apoptosis, and affect kidney function. The emerging field of 'glycomedicine' aims to apply new insights into the structure and function of the glycome to therapy development, potentially improving immunological responses and optimizing therapeutic antibodies. The chapter also reviews key types of glycosylation, such as N-linked and O-linked glycans, and their roles in various biological processes, including immune responses, inflammation, and cancer. It discusses congenital disorders of glycosylation (CDGs) and their clinical manifestations, as well as the potential for dietary supplementation and personalized medicine to address these disorders. Additionally, it explores the impact of glycosylation on immunoglobulin functions and its role in cancer, including the mechanisms by which altered glycosylation patterns contribute to cancer development and progression.The chapter discusses the role of glycosylation in health and disease, highlighting the glycome as the complete repertoire of glycoconjugates composed of carbohydrate chains (glycans) covalently linked to lipid or protein molecules. Glycoconjugate synthesis is a dynamic process influenced by enzymes, sugar precursors, organelle structures, and cellular signals. Studies of rare genetic disorders affecting glycosylation have emphasized the biological importance of the glycome, and technological advancements have improved understanding of its complexity. Changes in glycosylation can modulate inflammatory responses, viral immune escape, cancer cell metastasis, and apoptosis, and affect kidney function. The emerging field of 'glycomedicine' aims to apply new insights into the structure and function of the glycome to therapy development, potentially improving immunological responses and optimizing therapeutic antibodies. The chapter also reviews key types of glycosylation, such as N-linked and O-linked glycans, and their roles in various biological processes, including immune responses, inflammation, and cancer. It discusses congenital disorders of glycosylation (CDGs) and their clinical manifestations, as well as the potential for dietary supplementation and personalized medicine to address these disorders. Additionally, it explores the impact of glycosylation on immunoglobulin functions and its role in cancer, including the mechanisms by which altered glycosylation patterns contribute to cancer development and progression.