A major resurgence of interest in the spin structure of the nucleon
followed the 1988 publication[1] of small-x measurements of 
by the European Muon Collaboration (EMC). Analysis
of the EMC data and larger-x deep-inelastic scattering (DIS) data from
SLAC[2] gave rise to the so-called ``spin crisis'' -- the
observation that the integral contribution of the up and down quarks to the proton's
helicity was small[3].
The past six years has seen an enormous effort to acquire more precise
DIS data using polarized electron and muon beams. New measurements of 
confirm[4] the earlier EMC results, and new data on the neutron from DIS on
polarized 
[5] and polarized 
[6] add significantly to our knowledge
of quark polarization in the nucleon system. The search for new
understanding continues. A major effort is underway at DESY where the HERMES[7]
experiment will extend DIS to more exclusive channels. Experiments are also envisioned at SLAC
using 50 GeV polarized electrons and at CEBAF exploiting parity violation.
In spite of the large body of new data and the promise of even better experiments in the near future, polarized DIS measurements have major limitations. They do not directly provide any information about antiquark or gluon helicity distributions. Neither can they probe the potentially equally interesting, and completely unknown, chiral-odd quark structure functions[8,9,10,11,12,13,14]; hence the interest in polarized hard-hadronic processes which could offer new physics insight, complimentary to polarized DIS[15,16].