Abstract. Schur functions are considered to be the most important basis for the ring of symmetric functions. Skew Schur functions are indexed by skew shapes and as symmetric functions they have a linear expansion over Schur functions where the structure coefficients are the Littlewood-Richardson coefficients. Interestingly, the partitions which appear in that expansion fit, in a certain sense, the skew shape and run over a subposet of the dominance lattice of partitions with bottom and top elements determined by that skew shape. I shall discuss some results, in collaboration with Conflitti and Mamede, on criteria for full support of a special class of ribbon shapes, which imply a recent classification of maximal connected skew shapes in the Schur positivity order by McNamara and van Willigenburg.