diff --git a/ndn-cpp/common.hpp b/ndn-cpp/common.hpp
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--- /dev/null
+++ b/ndn-cpp/common.hpp
@@ -0,0 +1,31 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2013, Regents of the University of California
+ *                     Alexander Afanasyev
+ *                     Zhenkai Zhu
+ *
+ * BSD license, See the LICENSE file for more information
+ *
+ * Author: Zhenkai Zhu <zhenkai@cs.ucla.edu>
+ *         Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ */
+
+#ifndef NDN_COMMON_HPP
+#define NDN_COMMON_HPP
+
+#include "../config.h"
+
+// Depending on where ./configure found shared_ptr, define the ptr_lib namespace.
+// We always use ndn::ptr_lib::shared_ptr.
+#if HAVE_STD_SHARED_PTR
+#include <memory>
+namespace ndn { namespace ptr_lib = std; }
+#elif HAVE_BOOST_SHARED_PTR
+#include <boost/shared_ptr.hpp>
+#include <boost/make_shared.hpp>
+namespace ndn { namespace ptr_lib = boost; }
+#else
+#error "Can't find shared_ptr in std or boost"
+#endif
+
+#endif