diff --git a/ndn-cpp/security/identity/private-key-storage.cpp b/ndn-cpp/security/identity/private-key-storage.cpp
new file mode 100644
index 0000000..4f2d0aa
--- /dev/null
+++ b/ndn-cpp/security/identity/private-key-storage.cpp
@@ -0,0 +1,23 @@
+/**
+ * @author: Jeff Thompson
+ * See COPYING for copyright and distribution information.
+ */
+
+#include "private-key-storage.hpp"
+
+using namespace std;
+
+namespace ndn {
+
+PrivateKeyStorage::~PrivateKeyStorage()
+{
+}
+
+// TODO: Move to subclass.
+Blob 
+PrivateKeyStorage::sign(const Blob& blob, const string& keyName, DigestAlgorithm digestAlgorithm)
+{
+  return Blob();
+}
+
+}