The objective of the present thesis is to define the construction with aunque, to study the modal selection involved in that construction, and to analyse two possible translations for it in French : the construction with bien que, and the construction with même si. After reviewing the various explanations proposed to account for the construction under study, it turns out that what defines a construction such as A aunque B is the presupposition of an underlying implicative relation according to which statement A implies the absence of statement B. The modal selection carried out in the clause with aunque is explained thanks to the opposition emerging in Spanish language between an actualising mode [canto, canté, cantaré] and a non-actualising mode [cantaba, cantaría, cante, cantara]. This new description of the forms of the verbal system in Spanish leads not only to a simpler, more general explanation of the mode used in this type of clauses, but also to a more objective one. The translation of such clauses entails taking into account the specific value of the verbal forms following aunque as well as the value to be attributed in language French to the phrasal conjunctions bien que and même si.
