diff --git a/ctf/core.lua b/ctf/core.lua
index 83a50ca..30fcd64 100644
--- a/ctf/core.lua
+++ b/ctf/core.lua
@@ -145,7 +145,8 @@ function ctf.init()
 	ctf._set("default_diplo_state",        "war")
 	ctf._set("hud",                        true)
 	ctf._set("remove_player_on_leave",     false)
-	ctf._set("autoalloc_on_joinplayer",     true)
+	ctf._set("autoalloc_on_joinplayer",    true)
+	ctf._set("friendly_fire",              true)
 
 
 	for i = 1, #ctf.registered_on_init do
diff --git a/ctf/teams.lua b/ctf/teams.lua
index 88f3e3e..61587a3 100644
--- a/ctf/teams.lua
+++ b/ctf/teams.lua
@@ -420,3 +420,14 @@ minetest.register_on_leaveplayer(function(player)
 		ctf.remove_player(player:get_player_name())
 	end
 end)
+
+-- Disable friendly fire.
+minetest.register_on_punchplayer(function(player, hitter)
+	local to = ctf.player(player:get_player_name())
+	local from = ctf.player(hitter:get_player_name())
+
+	if not ctf.setting("friendly_fire") and to.team == from.team and
+			to.team ~= "" and to.team ~= nil then
+		return true
+	end
+end)