Official letters (công văn) are regarded as administrative documents (văn bản hành chính) as opposed to a legal instrument and are intended to contain correspondences from various authorities. However, in practice, in official letters addressed to other authorities or companies, many authorities express their views and interpretations of a legal provision. In many cases, Government authorities even give instruction on how certain issues should be addressed if there is no law regarding such issue or the law is not clear.
Accordingly, although official letters are not legal instruments and do not have the force of law, in practice, official letters provide useful interpretive aid and guidance for lawyers and practitioners in Vietnam. The downside of relying on official letters is that they are not always publicly available and the view or interpretation contained in an official letter can be changed in the future or conflict with other official letters or legal instruments. An official letter issued by one authority may not bind another authority if the other authority is not under control of the issuing authority.