diff --git a/gemp-lotr/gemp-lotr-server/src/main/java/com/gempukku/lotro/db/DeckDAO.java b/gemp-lotr/gemp-lotr-server/src/main/java/com/gempukku/lotro/db/DeckDAO.java
index c7c78a9aa..ee0c03952 100644
--- a/gemp-lotr/gemp-lotr-server/src/main/java/com/gempukku/lotro/db/DeckDAO.java
+++ b/gemp-lotr/gemp-lotr-server/src/main/java/com/gempukku/lotro/db/DeckDAO.java
@@ -8,14 +8,14 @@ import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.util.Arrays;
-import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 
 public class DeckDAO {
     private DbAccess _dbAccess;
 
-    private Map<Integer, Map<String, Deck>> _decks = new HashMap<Integer, Map<String, Deck>>();
+    private Map<Integer, Map<String, Deck>> _decks = new ConcurrentHashMap<Integer, Map<String, Deck>>();
 
     public DeckDAO(DbAccess dbAccess) {
         _dbAccess = dbAccess;
@@ -33,7 +33,7 @@ public class DeckDAO {
         if (deck != null) {
             Map<String, Deck> decksByType = _decks.get(player.getId());
             if (decksByType == null) {
-                decksByType = new HashMap<String, Deck>();
+                decksByType = new ConcurrentHashMap<String, Deck>();
                 _decks.put(player.getId(), decksByType);
             }
             decksByType.put(type, deck);
@@ -46,7 +46,7 @@ public class DeckDAO {
         storeDeckToDB(player.getId(), type, deck);
         Map<String, Deck> decksByType = _decks.get(player.getId());
         if (decksByType == null) {
-            decksByType = new HashMap<String, Deck>();
+            decksByType = new ConcurrentHashMap<String, Deck>();
             _decks.put(player.getId(), decksByType);
         }
         decksByType.put(type, deck);
diff --git a/gemp-lotr/gemp-lotr-server/src/main/java/com/gempukku/lotro/db/PlayerDAO.java b/gemp-lotr/gemp-lotr-server/src/main/java/com/gempukku/lotro/db/PlayerDAO.java
index 389eacd9b..d2ede5593 100644
--- a/gemp-lotr/gemp-lotr-server/src/main/java/com/gempukku/lotro/db/PlayerDAO.java
+++ b/gemp-lotr/gemp-lotr-server/src/main/java/com/gempukku/lotro/db/PlayerDAO.java
@@ -6,12 +6,12 @@ import java.sql.Connection;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
-import java.util.HashMap;
 import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 
 public class PlayerDAO {
     private DbAccess _dbAccess;
-    private Map<String, Player> _players = new HashMap<String, Player>();
+    private Map<String, Player> _players = new ConcurrentHashMap<String, Player>();
 
     public PlayerDAO(DbAccess dbAccess) {
         _dbAccess = dbAccess;