diff --git a/README.rst b/README.rst
index bb14be60e..9856370bc 100644
--- a/README.rst
+++ b/README.rst
@@ -22,7 +22,9 @@ This has been implemented:
 
 - Options dialog
 
-- Sending coins
+- Sending coins (including ask for fee when needed)
+
+- Show messages from core
 
 This has to be done:
 
@@ -34,6 +36,4 @@ This has to be done:
 
 - Show details dialog for transactions (on double click)
 
-- Display error messages/alerts from core
-
 - More thorough testing of the view with all the kinds of transactions (sendmany, generation)
diff --git a/gui/include/bitcoingui.h b/gui/include/bitcoingui.h
index c2c786b28..ab7b4bbdb 100644
--- a/gui/include/bitcoingui.h
+++ b/gui/include/bitcoingui.h
@@ -66,6 +66,7 @@ public slots:
     void setNumBlocks(int count);
     void setNumTransactions(int count);
     void error(const QString &title, const QString &message);
+    void askFee(qint64 nFeeRequired, bool *payFee);
 
 private slots:
     void sendcoinsClicked();
diff --git a/gui/src/bitcoin.cpp b/gui/src/bitcoin.cpp
index a1b74d879..6dbcb6c29 100644
--- a/gui/src/bitcoin.cpp
+++ b/gui/src/bitcoin.cpp
@@ -5,10 +5,12 @@
 #include "clientmodel.h"
 #include "util.h"
 #include "init.h"
+#include "main.h"
 #include "externui.h"
 
 #include <QApplication>
 #include <QMessageBox>
+#include <QThread>
 
 // Need a global reference for the notifications to find the GUI
 BitcoinGUI *guiref;
@@ -16,7 +18,6 @@ BitcoinGUI *guiref;
 int MyMessageBox(const std::string& message, const std::string& caption, int style, wxWindow* parent, int x, int y)
 {
     // Message from main thread
-    printf("MyMessageBox\n");
     if(guiref)
     {
         guiref->error(QString::fromStdString(caption),
@@ -50,9 +51,26 @@ int ThreadSafeMessageBox(const std::string& message, const std::string& caption,
 
 bool ThreadSafeAskFee(int64 nFeeRequired, const std::string& strCaption, wxWindow* parent)
 {
-    // Query from network thread
-    // TODO
-    return true;
+    if(!guiref)
+        return false;
+    if(nFeeRequired < MIN_TX_FEE || nFeeRequired <= nTransactionFee || fDaemon)
+        return true;
+    bool payFee = false;
+
+    /* Call slot on GUI thread.
+       If called from another thread, use a blocking QueuedConnection.
+     */
+    Qt::ConnectionType connectionType = Qt::DirectConnection;
+    if(QThread::currentThread() != QCoreApplication::instance()->thread())
+    {
+        connectionType = Qt::BlockingQueuedConnection;
+    }
+
+    QMetaObject::invokeMethod(guiref, "askFee", connectionType,
+                               Q_ARG(qint64, nFeeRequired),
+                               Q_ARG(bool*, &payFee));
+
+    return payFee;
 }
 
 void CalledSetStatusBar(const std::string& strText, int nField)
@@ -73,13 +91,13 @@ int main(int argc, char *argv[])
 {
     QApplication app(argc, argv);
     app.setQuitOnLastWindowClosed(false);
-    BitcoinGUI window;
-    guiref = &window;
 
     try {
         if(AppInit2(argc, argv))
         {
+            BitcoinGUI window;
             ClientModel model;
+            guiref = &window;
             window.setModel(&model);
 
             window.show();
diff --git a/gui/src/bitcoingui.cpp b/gui/src/bitcoingui.cpp
index b68720462..70da0b239 100644
--- a/gui/src/bitcoingui.cpp
+++ b/gui/src/bitcoingui.cpp
@@ -380,3 +380,15 @@ void BitcoinGUI::closeEvent(QCloseEvent *event)
     }
     QMainWindow::closeEvent(event);
 }
+
+void BitcoinGUI::askFee(qint64 nFeeRequired, bool *payFee)
+{
+    QString strMessage =
+        tr("This transaction is over the size limit.  You can still send it for a fee of %1, "
+          "which goes to the nodes that process your transaction and helps to support the network.  "
+          "Do you want to pay the fee?").arg(QString::fromStdString(FormatMoney(nFeeRequired)));
+    QMessageBox::StandardButton retval = QMessageBox::question(
+          this, tr("Sending..."), strMessage,
+          QMessageBox::Yes|QMessageBox::Cancel, QMessageBox::Yes);
+    *payFee = (retval == QMessageBox::Yes);
+}