diff --git a/library/storage_common.h b/library/storage_common.h
new file mode 100644
index 0000000..07cb6e9
--- /dev/null
+++ b/library/storage_common.h
@@ -0,0 +1,58 @@
+/*  Copyright (C) 2019, ARM Limited, All Rights Reserved
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Licensed 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.
+ */
+
+/** @file
+@brief This file includes common definitions for PSA storage
+*/
+
+#ifndef __PSA_STORAGE_COMMON_H__
+#define __PSA_STORAGE_COMMON_H__
+
+#include <stddef.h>
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** \brief Flags used when creating a data entry
+ */
+typedef uint32_t psa_storage_create_flags_t;
+
+/** \brief A type for UIDs used for identifying data
+ */
+typedef uint64_t psa_storage_uid_t;
+
+#define PSA_STORAGE_FLAG_NONE        0         /**< No flags to pass */
+#define PSA_STORAGE_FLAG_WRITE_ONCE (1 << 0) /**< The data associated with the uid will not be able to be modified or deleted. Intended to be used to set bits in `psa_storage_create_flags_t`*/
+
+/**
+ * \brief A container for metadata associated with a specific uid
+ */
+struct psa_storage_info_t {
+    uint32_t size;                  /**< The size of the data associated with a uid **/
+    psa_storage_create_flags_t flags;    /**< The flags set when the uid was created **/
+};
+
+/** Flag indicating that \ref psa_storage_create and \ref psa_storage_set_extended are supported */
+#define PSA_STORAGE_SUPPORT_SET_EXTENDED (1 << 0)
+
+/** \brief PSA storage specific error codes
+ */
+#define PSA_ERROR_INVALID_SIGNATURE     ((psa_status_t)-149)
+#define PSA_ERROR_DATA_CORRUPT          ((psa_status_t)-152)
+
+#endif // __PSA_STORAGE_COMMON_H__