If you intend to work in the Netherlands, you must first apply for a Citizen Service Number (Burger Servicenummer or, in short, BSN). The BSN is necessary for deducting your taxes and social security contributions. From November 2007 onwards, you will automatically receive a BSN when you register with City Hall. Otherwise you can personally pick up your BSN from the City Hall 10 days after having registered. You do not need to make an appointment to pick up the BSN at the City Hall.
Cross border workers still need apply for the BSN at tax office (Belastingdienst) after having registered with the local City Hall. To pick up their BSN, cross border workers need to make an appointment at the tax office first!