Are you going to marry abroad? In that case, first contact the foreign authorities who are going to marry you. They may indicate what documents you require to be able to get married.
Certificate of capacity to contract marriage
For some countries you will require a certificate of capacity to contract marriage. This is a certificate issued by the municipality allowing you to get married abroad. You must apply for such a certificate with the municipality in which you are a resident.
Registering a foreign marriage
Were you married abroad and are you now living in the Netherlands? In that case you must arrange for registration of your foreign marriage with the municipality.