Fibrations between finite topological spaces

We study Hurewicz fibrations between finite T${}_0$–spaces from a combinatorial viewpoint and give strong conditions that a continuous map between finite T${}_0$–spaces must satisfy in order to be a Hurewicz fibration. We also show that there exists a strong relationship between Hurewicz fibrations between finite T${}_0$–spaces and Grothendieck bifibrations. Finally we give several interesting examples that illustrate this theory and show that many of the assumptions of our results are necessary.