In 2004, the first edition of this manual, compiling comprehensive information on a range of aspects related to language proficiency training and testing, was published in order to support Statesâ efforts to comply with the strengthened provisions for language proficiency. In 2007, the ICAO Assembly adopted Assembly Resolution A36-11, Proficiency in the English language used for radiotelephony communications, which directed the Council to support Contracting States in their implementation of the language proficiency requirements by supporting globally harmonized language testing criteria. This second edition has been updated and reorganized into seven chapters and eight appendices, which have been significantly augmented. Several appendices have been formatted to facilitate the detachment of certain documents (checklists and tips) for reproduction and use as practical tools by stakeholders.