An ensemble Monte Carlo method is used to simulate electron transport through narrow high field regions which occur in planar‐doped barrier devices. These structures can achieve average velocities substantially higher than the static drift velocity corresponding to average electric field. Increased velocities in these structures arise primarily from two physical mechanisms. These mechanisms are (1) velocity overshoot and related ensemble hot electroneffects, and (2) an ensemble effect due to the collecting nature of the low field/high field boundary, which is not due to hot electrons. Ballistic‐like transport can occur through narrow high field spikes. However, ballistic transport is not the major contributor to high ensemble average velocities due to scattering in regions adjacent to the high field spike. Ensemble average velocities at a given point in a device are influenced by the field distribution ahead of this point as well as that behind it.