When a Spamhaus check reveals that you are on a Spamhaus blocklist (sometimes mistakenly called a blacklist), what should you do? The Spamhaus Project maintains a few different blocklists, such as the Spamhaus SBL and the DBL, and for each Spamhaus blocklist removal entails a couple of steps which may differ between the lists, but which are similar and not difficult. Note that most of these blocklists are DNSBLs (DNS-based blocklists), which means that what gets listed on them is IP addresses, specifically IP addresses demonstrated to be the sources of spam. All told, the Spamhaus Project maintains five primary lists, four of which are DNS-based blocklists (the Spamhaus SBL, the Spamhaus XBL, the Spamhaus PBL, and the Spamhaus DBL, plus Spamhaus Zen, which is a compilation of all four of those lists), and one of which, ROKSO, is a text-based, human-readable list of known (indeed notorious) spam operations. We'll explain each of these in turn, then explain how to go about getting removed from them.