diff --git a/include/psa/crypto_struct.h b/include/psa/crypto_struct.h
index 8987840..eba4862 100644
--- a/include/psa/crypto_struct.h
+++ b/include/psa/crypto_struct.h
@@ -82,6 +82,8 @@
     int iv_required : 1;
     int iv_set : 1;
     int has_input : 1;
+    int key_usage_sign : 1;
+    int key_usage_verify : 1;
     uint8_t mac_size;
     union
     {
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 3ea87f6..483e1a6 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -96,6 +96,7 @@
 
 typedef struct {
     psa_key_type_t type;
+    psa_key_policy_t policy;
     union {
         struct raw_data {
             uint8_t *data;
@@ -468,6 +469,9 @@
     if( slot->type == PSA_KEY_TYPE_NONE )
         return( PSA_ERROR_EMPTY_SLOT );
 
+    if( !( slot->policy.usage & PSA_KEY_USAGE_EXPORT ) )
+        return( PSA_ERROR_NOT_PERMITTED );
+
     if( PSA_KEY_TYPE_IS_RAW_BYTES( slot->type ) )
     {
         if( slot->data.raw.bytes > data_size )
@@ -982,6 +986,12 @@
         return( status );
     slot = &global_data.key_slots[key];
 
+    if ( ( slot->policy.usage & PSA_KEY_USAGE_SIGN ) != 0 )
+        operation->key_usage_sign = 1;
+
+    if ( ( slot->policy.usage & PSA_KEY_USAGE_VERIFY ) != 0 )
+        operation->key_usage_verify = 1;
+
     if( ! PSA_ALG_IS_HMAC( alg ) )
     {
         cipher_info = mbedtls_cipher_info_from_psa( alg, key_type, key_bits );
@@ -1080,7 +1090,7 @@
     return( mbedtls_to_psa_error( ret ) );
 }
 
-psa_status_t psa_mac_finish( psa_mac_operation_t *operation,
+static psa_status_t psa_mac_finish_internal( psa_mac_operation_t *operation,
                              uint8_t *mac,
                              size_t mac_size,
                              size_t *mac_length )
@@ -1132,6 +1142,17 @@
     }
 }
 
+psa_status_t psa_mac_finish( psa_mac_operation_t *operation,
+                             uint8_t *mac,
+                             size_t mac_size,
+                             size_t *mac_length )
+{
+    if( !( operation->key_usage_sign ) )
+        return( PSA_ERROR_NOT_PERMITTED );
+
+    return( psa_mac_finish_internal(operation, mac, mac_size, mac_length ) );
+}
+
 #define MBEDTLS_PSA_MAC_MAX_SIZE                       \
     ( MBEDTLS_MD_MAX_SIZE > MBEDTLS_MAX_BLOCK_LENGTH ? \
       MBEDTLS_MD_MAX_SIZE :                            \
@@ -1142,9 +1163,14 @@
 {
     uint8_t actual_mac[MBEDTLS_PSA_MAC_MAX_SIZE];
     size_t actual_mac_length;
-    psa_status_t status = psa_mac_finish( operation,
-                                          actual_mac, sizeof( actual_mac ),
-                                          &actual_mac_length );
+    psa_status_t status;
+
+    if( !( operation->key_usage_verify ) )
+        return( PSA_ERROR_NOT_PERMITTED );
+
+    status = psa_mac_finish_internal( operation,
+                                      actual_mac, sizeof( actual_mac ),
+                                      &actual_mac_length );
     if( status != PSA_SUCCESS )
         return( status );
     if( actual_mac_length != mac_length )
@@ -1184,6 +1210,8 @@
         return( PSA_ERROR_EMPTY_SLOT );
     if( ! PSA_KEY_TYPE_IS_KEYPAIR( slot->type ) )
         return( PSA_ERROR_INVALID_ARGUMENT );
+    if( !( slot->policy.usage & PSA_KEY_USAGE_SIGN ) )
+        return( PSA_ERROR_NOT_PERMITTED );
 
 #if defined(MBEDTLS_RSA_C)
     if( slot->type == PSA_KEY_TYPE_RSA_KEYPAIR )
@@ -1260,6 +1288,69 @@
 }
 
 
+/****************************************************************/
+/* Key Policy */
+/****************************************************************/
+
+void psa_key_policy_init(psa_key_policy_t *policy)
+{
+    memset( policy, 0, sizeof( psa_key_policy_t ) );
+}
+
+void psa_key_policy_set_usage(psa_key_policy_t *policy,
+                              psa_key_usage_t usage,
+                              psa_algorithm_t alg)
+{
+    policy->usage = usage;
+    policy->alg = alg;
+}
+
+psa_key_usage_t psa_key_policy_get_usage(psa_key_policy_t *policy)
+{
+    return( policy->usage );
+}
+
+psa_algorithm_t psa_key_policy_get_algorithm(psa_key_policy_t *policy)
+{
+    return( policy->alg );
+}
+
+psa_status_t psa_set_key_policy(psa_key_slot_t key,
+                                const psa_key_policy_t *policy)
+{
+    key_slot_t *slot;
+
+    if( key == 0 || key > MBEDTLS_PSA_KEY_SLOT_COUNT || policy == NULL )
+        return( PSA_ERROR_INVALID_ARGUMENT );
+    
+    slot = &global_data.key_slots[key];
+    if( slot->type != PSA_KEY_TYPE_NONE )
+        return( PSA_ERROR_OCCUPIED_SLOT );
+
+    if( ( policy->usage & ~( PSA_KEY_USAGE_EXPORT | PSA_KEY_USAGE_ENCRYPT 
+                        | PSA_KEY_USAGE_DECRYPT | PSA_KEY_USAGE_SIGN 
+                        | PSA_KEY_USAGE_VERIFY ) ) != 0 )
+        return( PSA_ERROR_INVALID_ARGUMENT );
+
+    slot->policy = *policy;
+
+    return( PSA_SUCCESS );
+}
+
+psa_status_t psa_get_key_policy(psa_key_slot_t key,
+                                psa_key_policy_t *policy)
+{
+    key_slot_t *slot;
+
+    if( key == 0 || key > MBEDTLS_PSA_KEY_SLOT_COUNT || policy == NULL )
+        return( PSA_ERROR_INVALID_ARGUMENT );
+
+    slot = &global_data.key_slots[key];
+    
+    *policy = slot->policy;
+
+    return( PSA_SUCCESS );
+}
 
 /****************************************************************/
 /* Module setup */
diff --git a/tests/suites/test_suite_psa_crypto.data b/tests/suites/test_suite_psa_crypto.data
index 2de3df1..326f9fb 100644
--- a/tests/suites/test_suite_psa_crypto.data
+++ b/tests/suites/test_suite_psa_crypto.data
@@ -83,3 +83,12 @@
 
 PSA sign RSA PKCS#1 v1.5 SHA-256, output buffer too small
 sign_fail:PSA_KEY_TYPE_RSA_KEYPAIR:"3082025e02010002818100af057d396ee84fb75fdbb5c2b13c7fe5a654aa8aa2470b541ee1feb0b12d25c79711531249e1129628042dbbb6c120d1443524ef4c0e6e1d8956eeb2077af12349ddeee54483bc06c2c61948cd02b202e796aebd94d3a7cbf859c2c1819c324cb82b9cd34ede263a2abffe4733f077869e8660f7d6834da53d690ef7985f6bc3020301000102818100874bf0ffc2f2a71d14671ddd0171c954d7fdbf50281e4f6d99ea0e1ebcf82faa58e7b595ffb293d1abe17f110b37c48cc0f36c37e84d876621d327f64bbe08457d3ec4098ba2fa0a319fba411c2841ed7be83196a8cdf9daa5d00694bc335fc4c32217fe0488bce9cb7202e59468b1ead119000477db2ca797fac19eda3f58c1024100e2ab760841bb9d30a81d222de1eb7381d82214407f1b975cbbfe4e1a9467fd98adbd78f607836ca5be1928b9d160d97fd45c12d6b52e2c9871a174c66b488113024100c5ab27602159ae7d6f20c3c2ee851e46dc112e689e28d5fcbbf990a99ef8a90b8bb44fd36467e7fc1789ceb663abda338652c3c73f111774902e840565927091024100b6cdbd354f7df579a63b48b3643e353b84898777b48b15f94e0bfc0567a6ae5911d57ad6409cf7647bf96264e9bd87eb95e263b7110b9a1f9f94acced0fafa4d024071195eec37e8d257decfc672b07ae639f10cbb9b0c739d0c809968d644a94e3fd6ed9287077a14583f379058f76a8aecd43c62dc8c0f41766650d725275ac4a1024100bb32d133edc2e048d463388b7be9cb4be29f4b6250be603e70e3647501c97ddde20a4e71be95fd5e71784e25aca4baf25be5738aae59bbfe1c997781447a2b24":PSA_ALG_RSA_PKCS1V15_SIGN(PSA_ALG_SHA_256):"ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad":127:PSA_ERROR_BUFFER_TOO_SMALL
+
+PSA Key Policy set and get
+key_policy:PSA_KEY_USAGE_ENCRYPT:PSA_ALG_CBC_BASE
+
+PSA Key Policy enforcement - export
+key_policy_fail:PSA_KEY_USAGE_EXPORT:PSA_ALG_RSA_PKCS1V15_SIGN_RAW:PSA_ERROR_NOT_PERMITTED:"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"
+
+PSA Key Policy enforcement - sign
+key_policy_fail:PSA_KEY_USAGE_SIGN:PSA_ALG_RSA_PKCS1V15_SIGN_RAW:PSA_ERROR_NOT_PERMITTED:"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"
diff --git a/tests/suites/test_suite_psa_crypto.function b/tests/suites/test_suite_psa_crypto.function
index 9381794..ae5401a 100644
--- a/tests/suites/test_suite_psa_crypto.function
+++ b/tests/suites/test_suite_psa_crypto.function
@@ -68,6 +68,7 @@
     size_t reexported_length;
     psa_key_type_t got_type;
     size_t got_bits;
+    psa_key_policy_t policy = {0};
 
     data = unhexify_alloc( hex, &data_size );
     TEST_ASSERT( data != NULL );
@@ -81,6 +82,13 @@
     }
     TEST_ASSERT( psa_crypto_init( ) == PSA_SUCCESS );
 
+    psa_key_policy_init( &policy );
+
+    psa_key_policy_set_usage( &policy, PSA_KEY_USAGE_EXPORT, 
+                              PSA_ALG_VENDOR_FLAG );
+
+    TEST_ASSERT( psa_set_key_policy( slot, &policy ) == PSA_SUCCESS );
+
     /* Import the key */
     TEST_ASSERT( psa_import_key( slot, type,
                                  data, data_size ) == PSA_SUCCESS );
@@ -107,6 +115,8 @@
     }
     else
     {
+        TEST_ASSERT( psa_set_key_policy( slot2, &policy ) == PSA_SUCCESS );
+
         TEST_ASSERT( psa_import_key( slot2, type,
                                      exported, export_size ) ==
                      PSA_SUCCESS );
@@ -211,6 +221,7 @@
     unsigned char *expected_mac = NULL;
     size_t expected_mac_size;
     psa_mac_operation_t operation;
+    psa_key_policy_t policy;
 
     key = unhexify_alloc( key_hex, &key_size );
     TEST_ASSERT( key != NULL );
@@ -226,6 +237,12 @@
 
     TEST_ASSERT( psa_crypto_init( ) == PSA_SUCCESS );
 
+    psa_key_policy_init( &policy );
+
+    psa_key_policy_set_usage( &policy, PSA_KEY_USAGE_VERIFY, alg_arg );
+
+    TEST_ASSERT( psa_set_key_policy( key_slot, &policy ) == PSA_SUCCESS );
+
     TEST_ASSERT( psa_import_key( key_slot, key_type,
                                  key, key_size ) == PSA_SUCCESS );
     // TODO: support IV
@@ -276,6 +293,7 @@
     unsigned char *signature = NULL;
     size_t signature_size;
     size_t signature_length = 0xdeadbeef;
+    psa_key_policy_t policy = {0};
 
     key_data = unhexify_alloc( key_hex, &key_size );
     TEST_ASSERT( key_data != NULL );
@@ -286,6 +304,12 @@
 
     TEST_ASSERT( psa_crypto_init( ) == PSA_SUCCESS );
 
+    psa_key_policy_init( &policy );
+
+    psa_key_policy_set_usage( &policy, PSA_KEY_USAGE_SIGN, alg_arg );
+
+    TEST_ASSERT( psa_set_key_policy( slot, &policy ) == PSA_SUCCESS );
+
     TEST_ASSERT( psa_import_key( slot, key_type,
                                  key_data, key_size ) == PSA_SUCCESS );
     TEST_ASSERT( psa_get_key_information( slot,
@@ -331,6 +355,7 @@
     psa_status_t expected_status = expected_status_arg;
     unsigned char *signature = NULL;
     size_t signature_length = 0xdeadbeef;
+    psa_key_policy_t policy = {0};
 
     key_data = unhexify_alloc( key_hex, &key_size );
     TEST_ASSERT( key_data != NULL );
@@ -341,6 +366,12 @@
 
     TEST_ASSERT( psa_crypto_init( ) == PSA_SUCCESS );
 
+    psa_key_policy_init( &policy );
+
+    psa_key_policy_set_usage( &policy, PSA_KEY_USAGE_SIGN, alg_arg );
+
+    TEST_ASSERT( psa_set_key_policy( slot, &policy ) == PSA_SUCCESS );
+
     TEST_ASSERT( psa_import_key( slot, key_type,
                                  key_data, key_size ) == PSA_SUCCESS );
 
@@ -360,3 +391,88 @@
     mbedtls_psa_crypto_free( );
 }
 /* END_CASE */
+
+/* BEGIN_CASE */
+void key_policy( int usage_arg, int alg_arg )
+{
+    int key_slot = 1;
+    psa_key_type_t key_type = PSA_KEY_TYPE_AES;
+    unsigned char key[32] = {0};
+    psa_key_policy_t policy_set = {0};
+    psa_key_policy_t policy_get = {0};
+        
+    memset( key, 0x2a, sizeof( key ) );
+ 
+    TEST_ASSERT( psa_crypto_init( ) == PSA_SUCCESS );
+
+    psa_key_policy_init(& policy_set );
+    psa_key_policy_init(& policy_get );
+
+    psa_key_policy_set_usage( &policy_set, usage_arg, alg_arg );
+
+    TEST_ASSERT( psa_key_policy_get_usage( &policy_set ) == ( psa_key_usage_t )usage_arg );
+
+    TEST_ASSERT( psa_key_policy_get_algorithm( &policy_set) == ( psa_algorithm_t )alg_arg );
+
+    TEST_ASSERT( psa_set_key_policy( key_slot, &policy_set ) == PSA_SUCCESS );
+
+    TEST_ASSERT( psa_import_key( key_slot, key_type,
+                                 key, sizeof( key ) ) == PSA_SUCCESS );
+
+    TEST_ASSERT( psa_get_key_policy( key_slot, &policy_get ) == PSA_SUCCESS );
+
+    TEST_ASSERT( policy_get.usage == policy_set.usage );
+    TEST_ASSERT( policy_get.alg == policy_set.alg );
+
+exit:
+    psa_destroy_key( key_slot );
+    mbedtls_psa_crypto_free( );
+}
+/* END_CASE */
+
+/* BEGIN_CASE */
+void key_policy_fail( int usage_arg, int alg_arg, int expected_status, char *key_hex )
+{
+    int key_slot = 1;
+    unsigned char* keypair = NULL;
+    size_t key_size = 0;
+    size_t signature_length = 0;
+    psa_key_policy_t policy = {0};
+    int actual_status = PSA_SUCCESS;
+ 
+    TEST_ASSERT( psa_crypto_init( ) == PSA_SUCCESS );
+
+    psa_key_policy_init( &policy );
+
+    psa_key_policy_set_usage( &policy, usage_arg, alg_arg );
+
+    TEST_ASSERT( psa_set_key_policy( key_slot, &policy ) == PSA_SUCCESS );
+
+    if( usage_arg & PSA_KEY_USAGE_EXPORT )
+    {
+        keypair = unhexify_alloc( key_hex, &key_size );
+        TEST_ASSERT( keypair != NULL );
+        TEST_ASSERT( psa_import_key( key_slot, PSA_KEY_TYPE_RSA_KEYPAIR,
+                                keypair, key_size ) == PSA_SUCCESS );
+        actual_status = psa_asymmetric_sign( key_slot, 
+                        ( psa_algorithm_t )alg_arg, NULL, 0, NULL, 0, 
+                        NULL, 0, &signature_length );
+    }
+    
+    if( usage_arg & PSA_KEY_USAGE_SIGN )
+    {
+        keypair = unhexify_alloc( key_hex, &key_size );
+        TEST_ASSERT( keypair != NULL );
+        TEST_ASSERT( psa_import_key( key_slot, PSA_KEY_TYPE_RSA_KEYPAIR,
+                                keypair, key_size ) == PSA_SUCCESS );
+        actual_status = psa_export_key( key_slot, NULL, 0, NULL );
+    }
+
+    TEST_ASSERT( actual_status == expected_status );
+
+exit:
+    psa_destroy_key( key_slot );
+    mbedtls_free( keypair );
+    mbedtls_psa_crypto_free( );
+}
+/* END_CASE */