  In this Chapter the time-domain analysis of the velocity of the
electromagnetic field pulses generated by a spatially compact source in free
space is presented. Recent simulations and measurements of anomalous
superluminal, subluminal, and negative velocities are discussed. It is shown
that such velocities are local and instantaneous in nature and do not violate
either causality or special relativity. Although these effects are mainly
confined to the near- and intermediate-field zones, some of them seem
paradoxical and still lack adequate physical interpretation.
