diff --git a/conf/preferencesdialog.cpp b/conf/preferencesdialog.cpp
index 698dccd6c..f8558e090 100644
--- a/conf/preferencesdialog.cpp
+++ b/conf/preferencesdialog.cpp
@@ -24,6 +24,8 @@
 PreferencesDialog::PreferencesDialog( QWidget * parent, KConfigSkeleton * skeleton, Okular::EmbedMode embedMode )
     : KConfigDialog( parent, "preferences", skeleton )
 {
+    setWindowModality( Qt::ApplicationModal );
+
     m_general = new DlgGeneral( this, embedMode );
     m_performance = new DlgPerformance( this );
     m_accessibility = new DlgAccessibility( this );
diff --git a/part.cpp b/part.cpp
index 790175035..731ba5c52 100644
--- a/part.cpp
+++ b/part.cpp
@@ -1037,6 +1037,7 @@ void Part::slotGeneratorPreferences( )
 
     // we didn't find an instance of this dialog, so lets create it
     KConfigDialog * dialog = new KConfigDialog( m_pageView, "generator_prefs", Okular::Settings::self() );
+
     if( m_embedMode == ViewerWidgetMode )
     {
         dialog->setCaption( i18n( "Configure Viewer Backends" ) );
@@ -1048,6 +1049,7 @@ void Part::slotGeneratorPreferences( )
 
     m_document->fillConfigDialog( dialog );
 
+    dialog->setWindowModality( Qt::ApplicationModal );
     dialog->show();
 }