Abstract: A mechanism to generate flavour hierarchy via 5-dimensional wave-function localization is revisited in the context of an SO(10) grand unified theory. An extra-dimension compactified on an orbifold generates different zero-mode profiles for fermions of different charges. Utilizing suitable scalar fields, a predictive model for fermion masses and mixing is constructed and shown to be viable with the current data. All the Yukawa couplings in the model are of order unity while the hierarchies among different fermions result from the wave-function profiles. The naturalness of anarchical Yukawa couplings and predictions for various observables in the lepton sector will be discussed.