Robin Guilbot Title: Embedded mirror symmetry: beyond complete intersections Abstract: Mirror Symmetry for families of Calabi-Yau varieties is best understood in the case of complete intersections in Gorenstein Fano toric varieties. In this case, by Batyrev and Borisov work, Mirror Symmetry appears as a direct counterpart of natural dualities between polytopes. I will recall this beautiful construction and its Gross-Siebert enhancement by toric degenerations. Then I will present a generalization to a class of non complete intersection Calabi-Yau varieties that contains at least those defined by the 4 x 4 Pfaffians of a 5 x 5 skew symmetric matrix, and could be much wider.