diff --git a/src/Mtlstats/Types.hs b/src/Mtlstats/Types.hs
index 1c7849e..4d8f723 100644
--- a/src/Mtlstats/Types.hs
+++ b/src/Mtlstats/Types.hs
@@ -996,7 +996,15 @@ goalieIsActive g = g^.gYtd.gsMinsPlayed /= 0
 
 -- | Adds two sets of 'GoalieStats'
 addGoalieStats :: GoalieStats -> GoalieStats -> GoalieStats
-addGoalieStats = undefined
+addGoalieStats g1 g2 = GoalieStats
+  { _gsGames        = g1^.gsGames        + g2^.gsGames
+  , _gsMinsPlayed   = g1^.gsMinsPlayed   + g2^.gsMinsPlayed
+  , _gsGoalsAllowed = g1^.gsGoalsAllowed + g2^.gsGoalsAllowed
+  , _gsShutouts     = g1^.gsShutouts     + g2^.gsShutouts
+  , _gsWins         = g1^.gsWins         + g2^.gsWins
+  , _gsLosses       = g1^.gsLosses       + g2^.gsLosses
+  , _gsTies         = g1^.gsTies         + g2^.gsTies
+  }
 
 -- | Determines a goalie's average goals allowed per game.
 gsAverage :: GoalieStats -> Rational
diff --git a/test/TypesSpec.hs b/test/TypesSpec.hs
index a75e74a..e2c6f57 100644
--- a/test/TypesSpec.hs
+++ b/test/TypesSpec.hs
@@ -79,6 +79,7 @@ spec = describe "Mtlstats.Types" $ do
   goalieSearchExactSpec
   goalieSummarySpec
   goalieIsActiveSpec
+  addGoalieStatsSpec
   Menu.spec
 
 playerSpec :: Spec
@@ -772,6 +773,43 @@ goalieIsActiveSpec = describe "goalieIsActive" $ mapM_
     active = inactive
       & gYtd.gsMinsPlayed .~ 1
 
+addGoalieStatsSpec :: Spec
+addGoalieStatsSpec = describe "addGoalieStats" $ let
+  g1 = GoalieStats
+    { _gsGames        = 1
+    , _gsMinsPlayed   = 2
+    , _gsGoalsAllowed = 3
+    , _gsShutouts     = 4
+    , _gsWins         = 5
+    , _gsLosses       = 6
+    , _gsTies         = 7
+    }
+
+  g2 = GoalieStats
+    { _gsGames        = 8
+    , _gsMinsPlayed   = 9
+    , _gsGoalsAllowed = 10
+    , _gsShutouts     = 11
+    , _gsWins         = 12
+    , _gsLosses       = 13
+    , _gsTies         = 14
+    }
+
+  expected = GoalieStats
+    { _gsGames        = 9
+    , _gsMinsPlayed   = 11
+    , _gsGoalsAllowed = 13
+    , _gsShutouts     = 15
+    , _gsWins         = 17
+    , _gsLosses       = 19
+    , _gsTies         = 21
+    }
+
+  actual = g1 `addGoalieStats` g2
+
+  in it ("should be " ++ show expected) $
+    actual `shouldBe` expected
+
 joe :: Player
 joe = newPlayer 2 "Joe" "center"