Legalisation of documents
A document that is official and legal in one country is not necessarily official and legal in another. Many documents must therefore be legalised if you wish to use them abroad.
The legalisation process involves checking the origin of the relevant document. Legalisation is official confirmation that the signature of the civil servant that has signed a document, or the seal or stamp on the document, is legitimate.
It is not only the signature of the person that has issued the document that is legalised, the process can also legalise the signature of the legalising registrar. Every signature, every seal and every stamp will be legalised by the person authorised to do so and who is familiar with each signature, seal or stamp. This explains why various legalisations are sometimes required, in a specific order.
A country may have signed up to a legalisation treaty that encompasses agreements about how countries accept one another's official documents. Many countries have signed up to the Apostille Convention of The Hague of 5 October 1961. With this, just 1 legalisation is required via an apostille stamp.
You can find all the information on the website of the Federal Public Service Foreign Affairs.