diff --git a/src/gui/DatabaseTabWidget.cpp b/src/gui/DatabaseTabWidget.cpp
index 466cc484d..6a31f2cf2 100644
--- a/src/gui/DatabaseTabWidget.cpp
+++ b/src/gui/DatabaseTabWidget.cpp
@@ -19,6 +19,7 @@
 
 #include <QtCore/QFileInfo>
 #include <QtGui/QTabWidget>
+#include <QtGui/QMessageBox>
 
 #include "core/Database.h"
 #include "core/Metadata.h"
@@ -51,6 +52,8 @@ void DatabaseTabWidget::newDatabase()
     dbStruct.dbWidget = new DatabaseWidget(db, this);
 
     insertDatabase(db, dbStruct);
+
+    dbStruct.dbWidget->switchToMasterKeyChange();
 }
 
 void DatabaseTabWidget::openDatabase()
@@ -127,22 +130,42 @@ void DatabaseTabWidget::emitEntrySelectionChanged()
     Q_EMIT entrySelectionChanged(isSingleEntrySelected);
 }
 
-void DatabaseTabWidget::closeDatabase(Database* db)
+bool DatabaseTabWidget::closeDatabase(Database* db)
 {
     Q_ASSERT(db);
 
     const DatabaseManagerStruct& dbStruct = m_dbList.value(db);
-
-    if (dbStruct.modified) {
-        // TODO message box
-    }
-
     int index = databaseIndex(db);
     Q_ASSERT(index != -1);
+    if (dbStruct.modified) {
+        QMessageBox::StandardButton result =
+            QMessageBox::question(
+            this, tr("Save changes?"),
+            tr("\"%1\" was modified.\nSave changes?").arg(tabText(index)),
+            QMessageBox::Yes | QMessageBox::No | QMessageBox::Cancel, QMessageBox::Yes);
+        if (result == QMessageBox::Yes) {
+            saveDatabase(db);
+        }
+        else if (result == QMessageBox::Cancel) {
+            return false;
+        }
+    }
 
     removeTab(index);
+    m_dbList.remove(db);
+    delete dbStruct.file;
     delete dbStruct.dbWidget;
     delete db;
+    return true;
+}
+
+bool DatabaseTabWidget::closeAllDatabases() {
+    while (!m_dbList.isEmpty()) {
+        if (!closeDatabase()) {
+            return false;
+        }
+    }
+    return true;
 }
 
 void DatabaseTabWidget::saveDatabase(Database* db)
@@ -192,13 +215,21 @@ void DatabaseTabWidget::saveDatabaseAs(Database* db)
     }
 }
 
-void DatabaseTabWidget::closeDatabase(int index)
+bool DatabaseTabWidget::closeDatabase(int index)
 {
     if (index == -1) {
         index = currentIndex();
     }
 
-    closeDatabase(indexDatabase(index));
+    return closeDatabase(indexDatabase(index));
+}
+
+void DatabaseTabWidget::closeDatabaseFromSender()
+{
+    Q_ASSERT(sender());
+    DatabaseWidget* dbWidget = static_cast<DatabaseWidget*>(sender());
+    Database* db = databaseFromDatabaseWidget(dbWidget);
+    closeDatabase(db);
 }
 
 void DatabaseTabWidget::saveDatabase(int index)
@@ -272,7 +303,9 @@ void DatabaseTabWidget::updateTabName(Database* db)
             tabName = QString("%1 [%2]").arg(db->metadata()->name(), tr("New database"));
         }
     }
-
+    if (dbStruct.modified) {
+        tabName.append("*");
+    }
     setTabText(index, tabName);
 }
 
@@ -297,6 +330,19 @@ Database* DatabaseTabWidget::indexDatabase(int index)
     return 0;
 }
 
+Database* DatabaseTabWidget::databaseFromDatabaseWidget(DatabaseWidget* dbWidget)
+{
+    QHashIterator<Database*, DatabaseManagerStruct> i(m_dbList);
+    while (i.hasNext()) {
+        i.next();
+        if (i.value().dbWidget == dbWidget) {
+            return i.key();
+        }
+    }
+
+    return 0;
+}
+
 void DatabaseTabWidget::insertDatabase(Database* db, const DatabaseManagerStruct& dbStruct)
 {
     m_dbList.insert(db, dbStruct);
@@ -308,6 +354,8 @@ void DatabaseTabWidget::insertDatabase(Database* db, const DatabaseManagerStruct
 
     connect(db->metadata(), SIGNAL(nameTextChanged(Database*)), SLOT(updateTabName(Database*)));
     connect(dbStruct.dbWidget->entryView(), SIGNAL(entrySelectionChanged()), SLOT(emitEntrySelectionChanged()));
+    connect(dbStruct.dbWidget, SIGNAL(closeRequest()), SLOT(closeDatabase()));
+    connect(db, SIGNAL(modified()), SLOT(modified()));
 }
 
 DatabaseWidget* DatabaseTabWidget::currentDatabaseWidget()
@@ -320,3 +368,14 @@ DatabaseWidget* DatabaseTabWidget::currentDatabaseWidget()
         return 0;
     }
 }
+
+void DatabaseTabWidget::modified()
+{
+    Q_ASSERT(sender());
+    Database* db = static_cast<Database*>(sender());
+    DatabaseManagerStruct& dbStruct = m_dbList[db];
+    if (!dbStruct.modified) {
+        dbStruct.modified = true;
+        updateTabName(db);
+    }
+}
diff --git a/src/gui/DatabaseTabWidget.h b/src/gui/DatabaseTabWidget.h
index 9571f8f71..4f2dab161 100644
--- a/src/gui/DatabaseTabWidget.h
+++ b/src/gui/DatabaseTabWidget.h
@@ -54,7 +54,9 @@ public Q_SLOTS:
     void openDatabase();
     void saveDatabase(int index = -1);
     void saveDatabaseAs(int index = -1);
-    void closeDatabase(int index = -1);
+    bool closeDatabase(int index = -1);
+    void closeDatabaseFromSender();
+    bool closeAllDatabases();
     void changeMasterKey();
     void createEntry();
     void editEntry();
@@ -70,13 +72,15 @@ private Q_SLOTS:
     void openDatabaseRead();
     void openDatabaseCleanup();
     void emitEntrySelectionChanged();
+    void modified();
 
 private:
     void saveDatabase(Database* db);
     void saveDatabaseAs(Database* db);
-    void closeDatabase(Database* db);
+    bool closeDatabase(Database* db);
     int databaseIndex(Database* db);
     Database* indexDatabase(int index);
+    Database* databaseFromDatabaseWidget(DatabaseWidget* dbWidget);
     void insertDatabase(Database* db, const DatabaseManagerStruct& dbStruct);
 
     QWidget* m_window;
diff --git a/src/gui/DatabaseWidget.cpp b/src/gui/DatabaseWidget.cpp
index 19f6584fc..f3980b952 100644
--- a/src/gui/DatabaseWidget.cpp
+++ b/src/gui/DatabaseWidget.cpp
@@ -155,6 +155,11 @@ void DatabaseWidget::updateMasterKey(bool accepted)
 {
     if (accepted) {
         m_db->setKey(m_changeMasterKeyWidget->newMasterKey());
+
+    }
+    else if (m_db->transformedMasterKey().isEmpty()) { // TODO other test?
+        Q_EMIT closeRequest();
+        return;
     }
 
     setCurrentIndex(0);
diff --git a/src/gui/DatabaseWidget.h b/src/gui/DatabaseWidget.h
index d5034b990..ca564917e 100644
--- a/src/gui/DatabaseWidget.h
+++ b/src/gui/DatabaseWidget.h
@@ -38,6 +38,9 @@ public:
     GroupView* groupView();
     EntryView* entryView();
 
+Q_SIGNALS:
+    void closeRequest();
+
 public Q_SLOTS:
     void createEntry();
     void createGroup();
diff --git a/src/gui/MainWindow.cpp b/src/gui/MainWindow.cpp
index 5a8ca783f..f9375b078 100644
--- a/src/gui/MainWindow.cpp
+++ b/src/gui/MainWindow.cpp
@@ -18,6 +18,8 @@
 #include "MainWindow.h"
 #include "ui_MainWindow.h"
 
+#include <QtGui/QCloseEvent>
+
 #include "core/Database.h"
 #include "core/DataPath.h"
 #include "core/Metadata.h"
@@ -63,3 +65,13 @@ void MainWindow::currentTabChanged(int index)
     m_ui->actionGroupEdit->setEnabled(hasTab);
     m_ui->actionChangeMasterKey->setEnabled(hasTab);
 }
+
+void MainWindow::closeEvent(QCloseEvent *event) {
+    if (!m_ui->tabWidget->closeAllDatabases()) {
+        event->ignore();
+    }
+    else {
+        event->accept();
+    }
+}
+
diff --git a/src/gui/MainWindow.h b/src/gui/MainWindow.h
index b4185660f..42f4ba3c0 100644
--- a/src/gui/MainWindow.h
+++ b/src/gui/MainWindow.h
@@ -32,6 +32,9 @@ public:
     MainWindow();
     ~MainWindow();
 
+protected:
+     void closeEvent(QCloseEvent *event);
+
 private Q_SLOTS:
     void currentTabChanged(int index);