The establishment of Locus Specific Databases (LSDB) is a crucial aspect for the Human Genetics field and one of the aims of the Human Variation Project. We report the development of a publicly accessible LSDB for the NIPBL gene (http://www.lovd.nl/NIPBL) implicated in Cornelia de Lange Syndrome (CdLS). This rare disorder is characterized by developmental and growth retardation, typical facial features, limb anomalies, and multiple organ involvement. Mutations in the NIPBL gene, the product of which is involved in control of the cohesion complex, account for over half of the patients currently characterized. The NIPBL LSDB adopted the Leiden Open Variation database (LOVD) software platform, which enables the comprehensive Web-based listing and curation of sequence variations and associated phenotypical information. The NIPBL-LOVD database contains 199 unique mutations reported in 246 patients (last accessed April 2010). Information on phenotypic characteristics included in the database enabled further genotype-phenotype correlations, the most evident being the severe form of CdLS associated with premature termination codons in the NIPBL gene. In addition to the NIPBL LSDB, 50 novel mutations are described in detail, resulting from a collaborative multicenter study.