  We discuss a toy model in six dimensions that predicts two fermion
generations, natural mass hierarchy and intergenerational mixing. Matter is
described by vector-like six dimensional fermions, one per each irreducible
standard model representation. Two fermion generations arise from the
compactification mechanism, through orbifold projection. They are localized in
different regions of the compact space by a six dimensional mass term. Flavour
symmetry is broken via Yukawa couplings, with a Higgs vacuum expectation value
not constant in the extra space. A hierarchical spectrum is obtained from order
one dimensionless parameters of the six dimensional theory. The Cabibbo angle
arises from the soft breaking of six dimensional parity symmetry. We also
briefly discuss how the present model could be extended to cover the realistic
case.
