diff --git a/src/msgpackstream.cpp b/src/msgpackstream.cpp
index bbbcc37..d4d28b3 100644
--- a/src/msgpackstream.cpp
+++ b/src/msgpackstream.cpp
@@ -24,15 +24,15 @@
         return retVal;
 
 MsgPackStream::MsgPackStream() :
-    dev(0), owndev(false), q_status(Ok)
+    dev(0), owndev(false), q_status(Ok), flushWrites(false)
 { }
 
 MsgPackStream::MsgPackStream(QIODevice *d) :
-    dev(d), owndev(false), q_status(Ok)
+    dev(d), owndev(false), q_status(Ok), flushWrites(false)
 { }
 
 MsgPackStream::MsgPackStream(QByteArray *a, QIODevice::OpenMode mode) :
-    owndev(true), q_status(Ok)
+    owndev(true), q_status(Ok), flushWrites(false)
 {
     QBuffer *buf = new QBuffer(a);
     buf->open(mode);
@@ -40,7 +40,7 @@ MsgPackStream::MsgPackStream(QByteArray *a, QIODevice::OpenMode mode) :
 }
 
 MsgPackStream::MsgPackStream(const QByteArray &a) :
-    owndev(true), q_status(Ok)
+    owndev(true), q_status(Ok), flushWrites(false)
 {
     QBuffer *buf = new QBuffer();
     buf->setData(a);
@@ -87,6 +87,16 @@ void MsgPackStream::setStatus(Status status)
     q_status = status;
 }
 
+void MsgPackStream::setFlushWrites(bool flush)
+{
+    flushWrites = flush;
+}
+
+bool MsgPackStream::willFlushWrites()
+{
+    return flushWrites;
+}
+
 MsgPackStream &MsgPackStream::operator>>(bool &b)
 {
     CHECK_STREAM_PRECOND(*this)
@@ -503,6 +513,16 @@ bool MsgPackStream::writeBytes(const char *data, uint len)
             setStatus(WriteFailed);
             return false;
         }
+        /* Apparently on Windows, the buffer size for named pipes is 0, and
+         * any data that is written before the remote end reads it is
+         * dropped (!!) without error (see https://bugreports.qt.io/browse/QTBUG-18385).
+         * We must be very sure that the data has been written before we try
+         * another write. This degrades performance in other cases, so callers
+         * must enable this behavior explicitly.
+         */
+        if (this->flushWrites) {
+            dev->waitForBytesWritten(-1);
+        }
 
         /* Increment the write pointer and the total byte count. */
         data += thisWrite;
diff --git a/src/msgpackstream.h b/src/msgpackstream.h
index 37f7222..61cd440 100644
--- a/src/msgpackstream.h
+++ b/src/msgpackstream.h
@@ -26,6 +26,8 @@ class MSGPACK_EXPORT MsgPackStream
     Status status() const;
     void resetStatus();
     void setStatus(Status status);
+    void setFlushWrites(bool flushWrites);
+    bool willFlushWrites();
 
     MsgPackStream &operator>>(bool &b);
     MsgPackStream &operator>>(quint8 &u8);
@@ -60,6 +62,7 @@ class MSGPACK_EXPORT MsgPackStream
     QIODevice *dev;
     bool owndev;
     Status q_status;
+    bool flushWrites;
 
     bool unpack_longlong(qint64 &i64);
     bool unpack_ulonglong(quint64 &u64);