Background: Mental disorders are alterations in several functional domains of human beings that trigger greater morbidity and mortality if not adequately addressed. The International Classification of Diseases 11th Edition (ICD11) is a recently approved modern global system to guide clinical practice for these disorders and other conditions. State of the art: Despite the imminent implementation of this system in member states, the guidelines on its scientific basis, practice and importance in public health have been published in a scattered manner, with a mainly psychiatric medical target audience, hence, it is necessary to unify these guidelines in a single text. Therefore, the objective of this review was to analyze three associated aspects: (a) current knowledge of the subject, (b) its application in psychological practice, and (c) reflection on the implications for public health poli...