Abstract: The Giroux correspondence allows us to understand contact structures on 3-manifolds through open book decompositions, which is the data of an oriented surface with boundary and a mapping class that is identity near the boundary. Various monoids inside this mapping class group have been shown to correspond to geometric properties of the corresponding contact structures, such as Stein Fillability, Strong Fillability, Weak Fillability, Tightness etc. In the case of open books with planar (genus zero) pages, Fillability of the underlying contact manifold was shown by Wendl to correspond to the existence of positive factorizations of the mapping class -- this is not true in higher genus. In recent work, extending results of Lisi -- Van Horn-Morris -- Wendl, we showed that using Spinal open books, fillability of a contact 3-manifold can be interpreted as the existence of positive 'admissible' factorizations of a mapping class in the framed mapping class group of a planar surface. Using this, we have recovered and improved existing fillability results on some torus bundles and surgeries on torus knots, as well as classified the fillings of these manifolds. These are joint works with Hyunki Min and Luya Wang. The talk will introduce the notions of spinal open books and positive admissible factorizations, and hopefully provide some insight into the four-dimensional workings that lead to the results.