  Pulse profiles from X-ray pulsars often exhibit strong energy dependence and
both periodic and aperiodic variations with time. The great variety of profiles
observed in various sources, and even from individual sources, makes it
difficult to separate the numerous factors influencing the phase-dependence of
the X-ray emission. These factors include the system geometry and particularly
the photon energy and angle dependence of emission about the neutron star
poles.
  Comptonisation may play an important role in determining beam patterns and
hence pulse profiles in X-ray pulsars. A Monte Carlo simulation is used to
investigate the beaming due to Comptonisation in a simple accretion column
geometry. We apply the model to the extremely variable pulse profiles of the
high-magnetic field pulsar GX 1+4.
