diff --git a/plugins/Relay/config.py b/plugins/Relay/config.py
index de0f22f70..ad1ea15d2 100644
--- a/plugins/Relay/config.py
+++ b/plugins/Relay/config.py
@@ -44,6 +44,10 @@ def configure(advanced):
     use the 'start' command followed by the 'connect' command.  Use the 'help'
     command to see how these two commands should be used.""")
 
+class Ignores(registry.SpaceSeparatedListOf):
+    List = ircutils.IrcSet
+    Value = conf.ValidHostmask
+    
 class Networks(registry.SpaceSeparatedListOf):
     List = ircutils.IrcSet
     Value = registry.String
@@ -69,10 +73,13 @@ conf.registerChannelValue(Relay, 'punishOtherRelayBots',
 conf.registerGlobalValue(Relay, 'channels',
     conf.SpaceSeparatedSetOfChannels([], """Determines which channels the bot
     will relay in."""))
-conf.registerChannelValue(Relay.channels,
-    'joinOnAllNetworks', registry.Boolean(True, """Determines whether the bot
+conf.registerChannelValue(Relay.channels, 'joinOnAllNetworks',
+    registry.Boolean(True, """Determines whether the bot
     will always join the channel(s) it relays for on all networks the bot is
     connected to."""))
+conf.registerChannelValue(Relay, 'ignores',
+    Ignores([], """Determines what hostmasks will not be relayed on a
+    channel."""))
 conf.registerChannelValue(Relay, 'noticeNonPrivmsgs',
     registry.Boolean(False, """Determines whether the bot will used NOTICEs
     rather than PRIVMSGs for non-PRIVMSG relay messages (i.e., joins, parts,
diff --git a/plugins/Relay/plugin.py b/plugins/Relay/plugin.py
index 3e83c4009..ff296e6ea 100644
--- a/plugins/Relay/plugin.py
+++ b/plugins/Relay/plugin.py
@@ -344,6 +344,12 @@ class Relay(callbacks.Privmsg):
             irc = self._getRealIrc(irc)
             if channel not in self.registryValue('channels'):
                 return
+            ignores = self.registryValue('ignores', channel)
+            for ignore in ignores:
+                if ircutils.hostmaskPatternEqual(ignore, msg.prefix):
+                    self.log.debug('Refusing to relay %s, ignored by %s.',
+                                   msg.prefix, ignore)
+                    return
             if ircmsgs.isCtcp(msg) and \
                'AWAY' not in text and 'ACTION' not in text:
                 return
diff --git a/src/conf.py b/src/conf.py
index 3d2b2ac9e..d856f14ce 100644
--- a/src/conf.py
+++ b/src/conf.py
@@ -176,6 +176,13 @@ class ValidChannel(registry.String):
         else:
             registry.String.setValue(self, v)
 
+class ValidHostmask(registry.String):
+    """Value must be a valid user hostmask."""
+    def setValue(self, v):
+        if not ircutils.isUserHostmask(v):
+            self.error()
+        super(ValidHostmask, self).setValue(v)
+
 registerGlobalValue(supybot, 'nick',
    ValidNick('supybot', """Determines the bot's default nick."""))