On the Relations Between Polarized Structure Functions

The status of the twist–2 and the twist–3 integral relations between polarized structure functions in deep inelastic scattering for electromagnetic and electroweak interactions is reviewed. One novel integral relation for the twist–3 contributions can be tested in the upcoming high statistics measurements of the structure function $g_2(x,Q^2)$ in the range $Q^2 \gsim M_p^2$.