The IMGT/HLA database, established 10 years ago, is a comprehensive resource for the human major histocompatibility complex (MHC) sequences and related information. Located on chromosome 6p21.3, the HLA complex contains over 220 genes, many of which are highly polymorphic and play crucial roles in the immune system. The database, maintained by the HLA Informatics Group and the European Bioinformatics Institute, provides a searchable repository of curated HLA sequences, with the latest release including 3300 sequences. The website offers tools for sequence alignment, probe and primer design, and integration of data from the HLA Dictionary. Regular updates ensure the database remains current, facilitating research and clinical applications. The database's content has expanded significantly, from 964 alleles in its first release to over 3300 alleles in the latest, reflecting its importance in managing and expanding HLA nomenclature.The IMGT/HLA database, established 10 years ago, is a comprehensive resource for the human major histocompatibility complex (MHC) sequences and related information. Located on chromosome 6p21.3, the HLA complex contains over 220 genes, many of which are highly polymorphic and play crucial roles in the immune system. The database, maintained by the HLA Informatics Group and the European Bioinformatics Institute, provides a searchable repository of curated HLA sequences, with the latest release including 3300 sequences. The website offers tools for sequence alignment, probe and primer design, and integration of data from the HLA Dictionary. Regular updates ensure the database remains current, facilitating research and clinical applications. The database's content has expanded significantly, from 964 alleles in its first release to over 3300 alleles in the latest, reflecting its importance in managing and expanding HLA nomenclature.