diff --git a/irctest/server_tests/join.py b/irctest/server_tests/join.py
index 91efaae..9ccdeb3 100644
--- a/irctest/server_tests/join.py
+++ b/irctest/server_tests/join.py
@@ -200,3 +200,78 @@ class JoinTestCase(cases.BaseServerTestCase):
             fail_msg="Expected 1 error when joining channels '#valid' and 'inv@lid', "
             "got {got}",
         )
+
+    @cases.mark_specifications("RFC1459", "RFC2812", "Modern")
+    def testJoinKey(self):
+        """Joins a single channel with a key"""
+        self.connectClient("chanop")
+        self.joinChannel(1, "#chan")
+        self.sendLine(1, "MODE #chan +k key")
+        self.getMessages(1)
+
+        self.connectClient("joiner")
+        self.sendLine(2, "JOIN #chan key")
+        self.assertMessageMatch(
+            self.getMessage(2),
+            command="JOIN",
+            params=["#chan"],
+        )
+
+    @cases.mark_specifications("RFC1459", "RFC2812", "Modern")
+    def testJoinKeys(self):
+        """Joins two channels, both with keys"""
+        self.connectClient("chanop")
+        if self.targmax.get("JOIN", "1000") == "1":
+            raise runner.OptionalExtensionNotSupported("Multi-target JOIN")
+        self.joinChannel(1, "#chan1")
+        self.sendLine(1, "MODE #chan1 +k key1")
+        self.getMessages(1)
+        self.joinChannel(1, "#chan2")
+        self.sendLine(1, "MODE #chan2 +k key2")
+        self.getMessages(1)
+
+        self.connectClient("joiner")
+        self.sendLine(2, "JOIN #chan1,#chan2 key1,key2")
+        self.assertMessageMatch(
+            self.getMessage(2),
+            command="JOIN",
+            params=["#chan1"],
+        )
+        self.assertMessageMatch(
+            [
+                msg
+                for msg in self.getMessages(2)
+                if msg.command not in {RPL_NAMREPLY, RPL_ENDOFNAMES}
+            ][0],
+            command="JOIN",
+            params=["#chan2"],
+        )
+
+    @cases.mark_specifications("RFC1459", "RFC2812", "Modern")
+    def testJoinManySingleKey(self):
+        """Joins two channels, the first one has a key."""
+        self.connectClient("chanop")
+        if self.targmax.get("JOIN", "1000") == "1":
+            raise runner.OptionalExtensionNotSupported("Multi-target JOIN")
+        self.joinChannel(1, "#chan1")
+        self.sendLine(1, "MODE #chan1 +k key1")
+        self.getMessages(1)
+        self.joinChannel(1, "#chan2")
+        self.getMessages(1)
+
+        self.connectClient("joiner")
+        self.sendLine(2, "JOIN #chan1,#chan2 key1")
+        self.assertMessageMatch(
+            self.getMessage(2),
+            command="JOIN",
+            params=["#chan1"],
+        )
+        self.assertMessageMatch(
+            [
+                msg
+                for msg in self.getMessages(2)
+                if msg.command not in {RPL_NAMREPLY, RPL_ENDOFNAMES}
+            ][0],
+            command="JOIN",
+            params=["#chan2"],
+        )