  We estimate the Collins function at a low energy scale by calculating the
fragmentation of a quark into a pion at the one-loop level in the chiral
invariant model of Manohar and Georgi. We give a useful parametrization of our
results and we briefly discuss different spin and/or azimuthal asymmetries
containing the Collins function and measurable in semi-inclusive DIS and e+ e-
annihilation
