  We briefly describe the methods used in compiling a set of high galactic
latitude background data. The characteristics and limitations of the data which
affect their use as a template for analysing extended objects are described. We
briefly describe a spectral fitting analysis of the data which reveals a
normalisation for the extragalactic background of 11.4 keV / sq cm / s / sr,
which implies the fraction of hard X-ray background presently resolved by
various Chandra observations is towards the lower limit of their estimates.
