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diff --git a/qpid/cpp/include/qpid/client/FlowControl.h b/qpid/cpp/include/qpid/client/FlowControl.h
new file mode 100644
index 0000000000..bff7071b3b
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+++ b/qpid/cpp/include/qpid/client/FlowControl.h
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+#ifndef QPID_CLIENT_FLOWCONTROL_H
+#define QPID_CLIENT_FLOWCONTROL_H
+
+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ */
+
+#include <qpid/sys/IntegerTypes.h>
+
+namespace qpid {
+namespace client {
+
+/**
+ * Flow control works by associating a finite amount of "credit"
+ * with a subscription.
+ *
+ * Credit includes a message count and a byte count. Each message
+ * received decreases the message count by one, and the byte count by
+ * the size of the message. Either count can have the special value
+ * UNLIMITED which is never decreased.
+ *
+ * A subscription's credit is exhausted when the message count is 0 or
+ * the byte count is too small for the next available message. The
+ * subscription will not receive any further messages until is credit
+ * is renewed.
+ *
+ * In "window mode" credit is automatically renewed when a message is
+ * completed (which by default happens when it is accepted). In
+ * non-window mode credit is not automatically renewed, it must be
+ * explicitly re-set (@see Subscription)
+ */
+struct FlowControl {
+    static const uint32_t UNLIMITED=0xFFFFFFFF;
+    FlowControl(uint32_t messages_=0, uint32_t bytes_=0, bool window_=false)
+        : messages(messages_), bytes(bytes_), window(window_) {}
+
+    static FlowControl messageCredit(uint32_t messages_) { return FlowControl(messages_,UNLIMITED,false); }
+    static FlowControl messageWindow(uint32_t messages_) { return FlowControl(messages_,UNLIMITED,true); }
+    static FlowControl byteCredit(uint32_t bytes_) { return FlowControl(UNLIMITED,bytes_,false); }
+    static FlowControl byteWindow(uint32_t bytes_) { return FlowControl(UNLIMITED,bytes_,true); }
+    static FlowControl unlimited() { return FlowControl(UNLIMITED, UNLIMITED, false); }
+    static FlowControl zero() { return FlowControl(0, 0, false); }
+
+    /** Message credit: subscription can accept up to this many messages. */
+    uint32_t messages;
+    /** Byte credit: subscription can accept up to this many bytes of message content. */
+    uint32_t bytes;
+    /** Window mode. If true credit is automatically renewed as messages are acknowledged. */
+    bool window;
+
+    bool operator==(const FlowControl& x) {
+        return messages == x.messages && bytes == x.bytes && window == x.window;
+    };
+};
+
+}} // namespace qpid::client
+
+#endif  /*!QPID_CLIENT_FLOWCONTROL_H*/