  Whether the X-ray luminosities of clusters of galaxies evolve has been a
contentious issue for over ten years. However, the data available to address
this issue have improved dramatically as cluster surveys from the ROSAT archive
near completion. There are now three samples of nearby clusters and seven
distant cluster samples. We present a uniform analysis of four of the distant
cluster samples. Each exhibits highly statistically significant luminosity
evolution. We combine three of these samples to measure the high redshift
cluster X-ray luminosity function with good statistics that shows the nature of
the evolution.
