diff --git a/src/yaku.erl b/src/yaku.erl
index 969aca1..0306827 100644
--- a/src/yaku.erl
+++ b/src/yaku.erl
@@ -18,6 +18,7 @@
          san_shoku_doujun/2,
          san_shoku_douko/2,
          san_kan_tsu/2,
+         toi_toi/2,
          kokushi_musou/2,
          ryuu_iisou/2,
          dai_san_gen/2]).
@@ -147,6 +148,13 @@ san_kan_tsu(#game{}, #player{hand=#hand{melds=Melds}}) ->
     Kans = [M || M = #meld{type=kan} <- Melds],
     length(Kans) =:= 3.
 
+%% @doc Returns true for a Toi toi hand
+%%      Hand must contain all triplets
+toi_toi(#game{}, #player{hand=#hand{melds=Melds}}) ->
+    Pons = [M || M = #meld{type=T} <- Melds,
+                  lists:member(T, [pon,kan])],
+    length(Pons) =:= 4.
+
 %% @doc Returns true for a 7-pair hand.
 -spec chiitoitsu(game(), player()) -> boolean().
 chiitoitsu(#game{}, #player{hand=#hand{tiles=[], melds=Melds}})
diff --git a/test/riichi_yaku_tests.erl b/test/riichi_yaku_tests.erl
index eedd93a..72fe07a 100644
--- a/test/riichi_yaku_tests.erl
+++ b/test/riichi_yaku_tests.erl
@@ -84,6 +84,15 @@ san_kan_tsu_test() ->
                         #meld{type=chii, tiles=[#tile{suit=man, value=V} || V <- [6,7,8]]}]},
     ?assertEqual(true, yaku:san_kan_tsu(#game{}, #player{hand=Hand, drawn={tsumo, #tile{suit=dragon, value=red}}})).
 
+toi_toi_test() ->
+    Hand = #hand{melds=[#meld{type=pair, tiles=lists:duplicate(2, #tile{suit=sou, value=8})},
+                        #meld{type=kan, tiles=[#tile{suit=sou, value=V} || V <- [1,1,1,1]]},
+                        #meld{type=kan, tiles=[#tile{suit=man, value=V} || V <- [1,1,1,1]]},
+                        #meld{type=pon, tiles=[#tile{suit=pin, value=V} || V <- [2,2,2]]},
+                        #meld{type=pon, tiles=[#tile{suit=pin, value=V} || V <- [8,8,8]]}]},
+    ?assertEqual(true, yaku:toi_toi(#game{}, #player{hand=Hand, drawn={tsumo, #tile{suit=dragon, value=red}}})).
+    
+
 chiitoitsu_test() ->
     Hand = #hand{melds=[#meld{type=pair, tiles=lists:duplicate(2, #tile{suit=pin, value=V})} || V <- lists:seq(1,7)]},
     ?assertEqual(true, yaku:chiitoitsu(#game{}, #player{hand=Hand})).