Whether a foreign adoption is recognised in the Netherlands depends on whether the country where the adoption was pronounced is party to the Hague Adoption Convention. By now, some 102 countries are affiliated and if the procedure in a convention country has gone well, that adoption is recognised in the Netherlands by operation of law. If this country is not party to the convention, this does not necessarily mean that the adoption will not be recognised.
According to Article 10:108 of the Dutch Civil Code, such an adoption can still be recognised by operation of law if both the child and the adoptive parents live outside the Netherlands. If the adoptive parents live in the Netherlands, a court ruling is required for recognition.
Incidentally, according to Article 10:105 of the Civil Code, it is also still possible for the Dutch court to pronounce the adoption if recognition fails in the Netherlands for whatever reason. If so, it will be fully reviewed in the Netherlands. This is a complicated matter, so be well informed by an expert lawyer from Küppers & Odekerken.