On 13 March 1908, the National Bureau for the Collection of Data on the Trade in Women and Girls was founded. The 47-year-old H.J.A. Simons de Ruyter was appointed National Police Commissioner. He proved to be the best person for the job owing to his passion for gathering and recording vital data, his knowledge of languages and his dedicated, helpful and generous personality. The Bureau and the police worked with women’s organisations to monitor activities and carry out checks at stations and ports where women and girls who could be exposed to a lewd lifestyle might be travelling. After legislation on morality was passed in 1911, the Bureau was given an additional task in 1914 to tackle trade in lewd publications. After the First World War erupted that year, there was not much more to do at the Bureau, which led Simons de Ruyter to support the immigration authorities in Amsterdam at his own request. This consisted mainly of finding accommodation, providing healthcare, food, clothing and financial assistance and helping to repatriate Belgian refugees.