There is a great deal of strong evidence that the nearby
radiogalaxy Centaurus A (NGC 5128) harbours an active galactic
nucleus at its centre. Apart from the radio emission, it possesses
a compact, variable hard X-ray source and infrared continuum
source at its nucleus. However, the simple idea that it is merely
an obscured quasar appears to be in conflict with more detailed
observations. Extensive study of the emission line filaments has
strongly suggested that the ionizing continuum is heavily beamed
in a direction away from us, and hence that Centaurus A may be a
BL Lac. This may also explain why no broad lines have been
observed in polarized light, despite the fact that the near IR
continuum is polarized, suggesting that some fraction of the
nuclear component is seen transmitted through the dusty regions.

We propose to perform observations which will, beyond doubt,
determine whether Centaurus A has a broad line region. Such a
conclusion is clearly vital to our understanding of this object
which, as the closest radiogalaxy, has been the subject of
extensive study and provides an obvious target for investigation
of AGN  unification schemes.