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United States Apostille

To simplify the difference between Hague and Non-Hague courtiers, let us say that you have a "Power of Attorney" issued in the United States, and you want to use it in Mexico, you have to sign your "POA" in front a notary then mail your document to your state to obtain an Apostille. That is all. Your document is ready for use in Mexico.
Let us say that you want to use your "POA" in Kuwait, you have to sign your "POA" in front a notary then mail your document to your state, because Kuwait is a Non-Hague country, most of the states will issue an Apostille, they will issue a regular certification, some states they issue Apostille (example California). Next step, you have to mail your "POA" to the U.S. Department of State in D.C. to obtain a federal authentication. Finally you mail it to the embassy of Kuwait who will certify the authentication of the U.S. Department of State. You may also need to obtain the stamp of the US Arab Chamber of Commerce.
Dealing between two Hague participating countries is simple and easy. Dealing with a Non-Hague participated countries is formal, and takes a long time.