The Hague Convention 1961: The primary international treaty governing apostille procedures, officially known as 'The Hague Convention of 5 October 1961 Abolishing the Requirement of Legalisation for Foreign Public Documents'

FCO Guidelines on Apostilles: Foreign & Commonwealth Office guidelines providing specific requirements for UK apostille procedures and document authentication

Commissioners for Oaths Act 1889: Legislation governing the notarisation requirements that must be fulfilled before a document can receive an apostille

Statutory Declarations Act 1835: Legislation that may be applicable if the authorisation letter requires statutory declaration as part of the authentication process

Powers of Attorney Act 1971: Relevant legislation when the authorisation letter involves delegating legal authority to another party

Companies Act 2006: Corporate legislation that may be applicable if the authorisation letter relates to company matters or corporate authority

Electronic Communications Act 2000: Legislation governing the use and validity of electronic signatures in legal documents