  We investigate models where gauge unification (GUT) proceeds in steps that
include Pati-Salam symmetry. Beyond the Standard Model, we allow for a
well-defined set of small representations of the GUT gauge group. We show that
all possible chains of Pati-Salam symmetry breaking can be realized in
accordance with gauge-coupling unification. We identify, in particular, models
with unification near the Planck scale, with intermediate left-right or SU(4)
quark-lepton symmetries that are relevant for flavor physics, with new colored
particles at accessible energies, and with an enlarged electroweak Higgs
sector. We look both at supersymmetric and non-supersymmetric scenarios.
