Register a short or long stay in Amsterdam with the municipality (gemeente), and receive your citizen service number (CSN).
When you register, you will receive a citizen service number (CSN) during your appointment. A CSN is required in order to be permitted to work, open a bank account, make use of a health care institution (a doctor or hospital) and to apply for benefits or an allowance. Note that is is very important to register the correct address and to notify the municipality on time if you change address.
If you are a highly skilled migrant, in many cases IN Amsterdam (formerly 'Expatcenter Amsterdam') can also help with these matters. They offer a streamlined procedure for arranging permits, CSN numbers and address registration.