We present the z = 0.3 - 0.7 cluster X-ray luminosity function ( XLF ) determined from the Southern SHARC ( Serendipitous High-redshift Archival ROSAT Cluster ) survey .
Over the luminosity range L \sim ( 0.3 - 3 ) \times 10 ^ { 44 } erg s ^ { -1 } ( 0.5 - 2.0 keV ) the XLF is in close agreement with that of the low redshift X-ray cluster population .
This result greatly strengthens our previous claim of no evolution of the cluster population , at these luminosities , at a median redshift of z = 0.44 .