The purpose of this manual is, on the one hand, to provide tax officials with the necessary tools to carry out their mission of mobilizing domestic tax revenue, and on the other hand, to provide, in complete transparency, clarifications for taxpayers wishing to inquire about the legal and regulatory administrative procedures in force. It aims to clarify all the operational relationships that taxpayers have with the tax administration, and functional ones, within the Directorate General of Taxes (DGI). The manual in no way replaces the General Tax Code (CGI) for legal interpretations, but refers to it. It facilitates access to official texts, recalls the general principles and explains the practical methods for implementing each procedure.