We present here the first results from the Chandra ERA (Environments of Radio-loud AGN) Large Project,
characterizing the cluster environments of a sample of 26 radio-loud active galactic nuclei (AGNs) at z ∼ 0.5
that covers three decades of radio luminosity. This is the first systematic X-ray environmental study at a single
epoch, and has allowed us to examine the relationship between radio luminosity and cluster environment without
the problems ofMalmquist bias.We have found a weak correlation between radio luminosity and host cluster X-ray
luminosity, as well as tentative evidence that this correlation is driven by the subpopulation of low-excitation radio
galaxies, with high-excitation radio galaxies showing no significant correlation. The considerable scatter in the
environments may be indicative of complex relationships not currently included in feedback models.