The book Expressing the Potential and the unreal in Latin, French and Romanian (published in 2015 by Editura Universitaria, Craiova) represents the doctoral thesis of Mrs. Cecilia Mihaela Popescu, defended 10 years ago and coordinated by Mrs. professor Dr. Maria Iliescu, PhD. The paper represents the first diachronic and contrastive study, detailed, on the ways of expressing potential cognitive values, respectively unreal/counterfactual in classical and late Latin, in French and Romanian, contributing first of all to the clarification of the respective notions in the specialised literature (from noematic and terminological point of view), but also of some aspects of morphosyntactic and semantic nature from the history of each analysed language. Throughout the operation, an attempt was made to demonstrate the thesis/theses of grammaticalization in the language: Latin, an Indo-European language, presents linguistic means similar to those in French and, respectively, Romanian, in terms of expressing POT and IR.