Robin Guilbot Title: Quasismoothness of hypersurfaces in toric varieties Abstract: A hypersurface Y in a toric variety X, given by a homogeneous equation f=0, is said to be quasismooth if the singular locus of f is contained in the irrelevant locus of X (e.g. the origin of A^{n+1} for X=P^n). This implies that the only singularities of Y are coming from the ambient variety X. In a joint work with M. Artebani and P. Comparin we give characterizations of quasismoothness for hypersurfaces in projective toric varieties, stated either in terms of Newton polytopes or in terms of the matrix of exponents of f. I will present these characterizations and their links with Mirror Symmetry in the case of anticanonical Calabi-Yau hypersurfaces.