  Intersecting Dp-branes often give rise to chiral fermions living on their
intersections. We study the construction of four-dimensional chiral gauge
theories by considering configurations of type II D(3+n)-branes wrapped on
non-trivial n-cycles on T^{2n} x(R^{2(3-n)}/Z_N), for n=1,2,3. The gauge
theories on the four non-compact dimensions of the brane world-volume are
generically chiral and non-supersymmetric. We analyze consistency conditions
(RR tadpole cancellation) for these models, and their relation to
four-dimensional anomaly cancellation. Cancellation of U(1) gauge anomalies
involves a Green-Schwarz mechanism mediated by RR partners of untwisted and/or
twisted moduli. This class of models is of potential phenomenological interest,
and we construct explicit examples of SU(3) x SU(2) x U(1) three-generation
models. The models are non-supersymmetric, but the string scale may be lowered
close to the weak scale so that the standard hierarchy problem is avoided. We
also comment on the presence of scalar tachyons and possible ways to avoid the
associated instabilities. We discuss the existence of (meta)stable
configurations of D-branes on 3-cycles in (T^2)^3, free of tachyons for certain
ranges of the six-torus moduli.
