Solid state polarized targets provide high polarization and high density
for many types of fixed targets employed by nuclear labs worldwide. 
Dynamic nuclear polarization and other RF techniques are
used to enhance the polarization of the cryogenically cooled solid
material to improve the figure of merit of the experiment.  A brief
discussion is given on methods  emphasis on recent
developments and observables.  A couple of experiments are discussed
providing examples of
implementation of this research which make it possible to access many
spin-dependent
degrees of freedom used to test fundamental prediction of QCD.