Nederland's Patriciaat, informally known as Het Blauwe Boekje (the blue book), is a book series published annually since 1910, containing the genealogies of important Dutch patrician non-noble families. It is issued by the Centraal Bureau voor Genealogie (CBG) in The Hague. The Publication Commission of the CBG determines which families are included. A family must have played an important role in the Dutch society during 150 years. The publication was modelled after the Genealogisches Handbuch bürgerlicher Familien.