The objective of this dissertation is to present an in-depth study of the chamber music works of Ernest Chausson., against the background of the composer's musical, cultural and esthetic environment. Chausson's chamber music output throws a new light sensitivity of a musician whose influence on the revitalization of late century French music cannot be denied. The first part of the dissertation is devoted to purely formal corpus analysis in order to explicit an objective sense of the composer's sound world. Part II emphasizes how the urge toward the greatest possible unity leads to the use of the cyclic form. Part III studies the dialogic modalities of various compositions, with a view to gaining more insight into Chausson 's musical thought. The last part focuses on the major esthetic trend of this time that may have influenced sorne of Chausson's musical gestures: Symbolism. Relevant historical writings and a range of current musicological approaches support and document each development.