diff --git a/include/hanabi_types.hpp b/include/hanabi_types.hpp
index 8fa10d3..da91613 100644
--- a/include/hanabi_types.hpp
+++ b/include/hanabi_types.hpp
@@ -102,6 +102,8 @@ namespace Hanabi
 
   std::ostream & operator<<(std::ostream & os, const Action & action);
 
+  std::ostream & operator<<(std::ostream & os, const ActionType & action_type);
+
 
   namespace Cards
   {
diff --git a/src/hanabi_types.cpp b/src/hanabi_types.cpp
index 5eda863..3a8aa4c 100644
--- a/src/hanabi_types.cpp
+++ b/src/hanabi_types.cpp
@@ -21,6 +21,35 @@ namespace Hanabi
     return os;
   }
 
+  std::ostream & operator<<(std::ostream & os, ActionType const & action_type)
+  {
+    switch (action_type)
+    {
+      case ActionType::play:
+        os << "play";
+        break;
+      case ActionType::discard:
+        os << "discard";
+        break;
+      case ActionType::color_clue:
+        os << "clue color";
+        break;
+      case ActionType::rank_clue:
+        os << "clue rank";
+        break;
+      case ActionType::end_game:
+        os << "end game";
+        break;
+      case ActionType::vote_terminate_players:
+        os << "vote termination";
+        break;
+      case ActionType::vote_terminate:
+        os << "terminate game";
+        break;
+    }
+    return os;
+  }
+
 
   std::string to_string(const Hanabi::Card & card)
   {