This is a technical explanation of the Convention between the United States and the Republic of Estonia signed on January 15, 1998. Paragraph 1 of Article 1 provides that the Convention applies to residents of the United States or Estonia except where the terms of the Convention provide otherwise. Under Article 4 (Resident) a person is generally treated as a resident of a Contracting State if that person is, under the laws of that State, liable to tax therein by reason of his domicile or other similar criteria. If, however, a person is considered a resident of both Contracting States, Article 4 provides rules for determining a single state of residence (or no state of residence). This determination governs for all purposes of the Convention.