We present evidence for relativistic bulk motion in powerful radio
sources. This motion continues to {\it kiloparsec} scales, indeed,
right to the sites of jet disruption. High quality, high resolution
radio continuum spectral maps of two samples of quasars and radio
galaxies show spectral asymmetries, srongly correlated to jet side in
the hotspot regions of the quasars only. This is most easily
interpreted, using Unified Schemes, as a relativistic effect. The
result is consistent with previous reported spectral asymmetries, and
resolves previous questions as to their origin. The lack of asymmetry
in spectral behaviour in the BLRG is noted, along with the problem
posed for the conventional place of BLRG in Unified Schemes, and
some suggestions made to resolve this apparent problem.