diff --git a/CHANGELOG.md b/CHANGELOG.md
index 64a5c564..d5dbae38 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,9 @@
 ## 4.3.0 (Expected: ~December 2019)
 
 ### Minor changes
+* Added "canonical" global namespace context: `nsctx_global`
+  * This is a normalized XML prefix:namespace pair vector computed from all loaded Yang modules. Useful when writing XML and XPATH expressions in callbacks.
+  * Get it with `clicon_nsctx_global_get(h)`
 * Added wildcard `*` as a mode to `CLICON_MODE` in clispec files
   * If you set "CLICON_MODE="*";" in a clispec file it means that syntax will appear in all CLI spec modes.
 * State callbacks provided by user are validated. If they are invalid an internal error is returned.
diff --git a/apps/backend/backend_main.c b/apps/backend/backend_main.c
index 3fe9603c..c6263576 100644
--- a/apps/backend/backend_main.c
+++ b/apps/backend/backend_main.c
@@ -92,6 +92,7 @@ backend_terminate(clicon_handle h)
     cxobj     *x;
     struct stat st;
     int        ss;
+    cvec      *nsctx;
 
     clicon_debug(1, "%s", __FUNCTION__);
     if ((ss = clicon_socket_get(h)) != -1)
@@ -108,6 +109,8 @@ backend_terminate(clicon_handle h)
 	xml_free(x);
     if ((yspec = clicon_dbspec_yang(h)) != NULL)
 	yspec_free(yspec);
+    if ((nsctx = clicon_nsctx_global_get(h)) != NULL)
+	cvec_free(nsctx);
     if ((yspec = clicon_config_yang(h)) != NULL)
 	yspec_free(yspec);
     if ((x = clicon_nacm_ext(h)) != NULL)
@@ -451,6 +454,7 @@ main(int    argc,
     int           ret;
     char         *dir;
     gid_t         gid = -1;
+    cvec         *nsctx_global = NULL; /* Global namespace context */
     
     /* In the startup, logs to stderr & syslog and debug flag set later */
     clicon_log_init(__PROGRAM__, LOG_INFO, logdst);
@@ -722,10 +726,10 @@ main(int    argc,
     if ((str = clicon_yang_main_dir(h)) != NULL)
 	if (yang_spec_load_dir(h, str, yspec) < 0)
 	    goto done;
-     /* Load clixon lib yang module */
+    /* Load clixon lib yang module */
     if (yang_spec_parse_module(h, "clixon-lib", NULL, yspec) < 0)
 	goto done;
-     /* Load yang module library, RFC7895 */
+    /* Load yang module library, RFC7895 */
     if (yang_modules_init(h) < 0)
 	goto done;
     /* Add netconf yang spec, used by netconf client and as internal protocol 
@@ -736,13 +740,21 @@ main(int    argc,
     if (yang_spec_parse_module(h, "ietf-restconf", NULL, yspec)< 0)
 	goto done;
     /* Load yang Restconf stream discovery */
-     if (clicon_option_bool(h, "CLICON_STREAM_DISCOVERY_RFC8040") &&
-	 yang_spec_parse_module(h, "ietf-restconf-monitoring", NULL, yspec)< 0)
-	 goto done;
-     /* Load yang Netconf stream discovery */
-     if (clicon_option_bool(h, "CLICON_STREAM_DISCOVERY_RFC5277") &&
-	 yang_spec_parse_module(h, "clixon-rfc5277", NULL, yspec)< 0)
-	 goto done;
+    if (clicon_option_bool(h, "CLICON_STREAM_DISCOVERY_RFC8040") &&
+	yang_spec_parse_module(h, "ietf-restconf-monitoring", NULL, yspec)< 0)
+	goto done;
+    /* Load yang Netconf stream discovery */
+    if (clicon_option_bool(h, "CLICON_STREAM_DISCOVERY_RFC5277") &&
+	yang_spec_parse_module(h, "clixon-rfc5277", NULL, yspec)< 0)
+	goto done;
+    /* Here all modules are loaded 
+     * Compute and set canonical namespace context
+     */
+    if (xml_nsctx_yangspec(yspec, &nsctx_global) < 0)
+	goto done;
+    if (clicon_nsctx_global_set(h, nsctx_global) < 0)
+	goto done;
+
     /* Initialize server socket and save it to handle */
     if (backend_rpc_init(h) < 0)
 	goto done;
@@ -895,7 +907,7 @@ main(int    argc,
 	goto done;
  ok:
     retval = 0;
-  done:
+ done:
     if (cbret)
 	cbuf_free(cbret);
     clicon_log(LOG_NOTICE, "%s: %u Terminated retval:%d", __PROGRAM__, getpid(), retval);
diff --git a/apps/cli/cli_main.c b/apps/cli/cli_main.c
index a9e2f7bf..c0981710 100644
--- a/apps/cli/cli_main.c
+++ b/apps/cli/cli_main.c
@@ -163,6 +163,7 @@ static int
 cli_terminate(clicon_handle h)
 {
     yang_stmt  *yspec;
+    cvec       *nsctx;
     cxobj      *x;
 
     clicon_rpc_close_session(h);
@@ -170,6 +171,8 @@ cli_terminate(clicon_handle h)
 	yspec_free(yspec);
     if ((yspec = clicon_config_yang(h)) != NULL)
 	yspec_free(yspec);
+    if ((nsctx = clicon_nsctx_global_get(h)) != NULL)
+	cvec_free(nsctx);
     if ((x = clicon_conf_xml(h)) != NULL)
 	xml_free(x);
     cli_plugin_finish(h);    
@@ -286,6 +289,7 @@ main(int argc, char **argv)
     int            tabmode;
     char          *dir;
     uint32_t       id = 0;
+    cvec          *nsctx_global = NULL; /* Global namespace context */
     
     /* Defaults */
     once = 0;
@@ -513,6 +517,14 @@ main(int argc, char **argv)
     if (netconf_module_load(h) < 0)
 	goto done;
     
+    /* Here all modules are loaded 
+     * Compute and set canonical namespace context
+     */
+    if (xml_nsctx_yangspec(yspec, &nsctx_global) < 0)
+	goto done;
+    if (clicon_nsctx_global_set(h, nsctx_global) < 0)
+	goto done;
+
     /* Create tree generated from dataspec. If no other trees exists, this is
      * the only one.
      * The following code creates the tree @datamodel
diff --git a/apps/netconf/netconf_main.c b/apps/netconf/netconf_main.c
index 02e8d94e..ec527cb8 100644
--- a/apps/netconf/netconf_main.c
+++ b/apps/netconf/netconf_main.c
@@ -323,6 +323,7 @@ static int
 netconf_terminate(clicon_handle h)
 {
     yang_stmt  *yspec;
+    cvec       *nsctx;
     cxobj      *x;
     
     clixon_plugin_exit(h);
@@ -332,6 +333,8 @@ netconf_terminate(clicon_handle h)
 	yspec_free(yspec);
     if ((yspec = clicon_config_yang(h)) != NULL)
 	yspec_free(yspec);
+    if ((nsctx = clicon_nsctx_global_get(h)) != NULL)
+	cvec_free(nsctx);
     if ((x = clicon_conf_xml(h)) != NULL)
 	xml_free(x);
     event_exit();
@@ -395,6 +398,7 @@ main(int    argc,
     yang_stmt       *yspecfg = NULL; /* For config XXX clixon bug */
     char            *str;
     uint32_t         id;
+    cvec            *nsctx_global = NULL; /* Global namespace context */
     
     /* Create handle */
     if ((h = clicon_handle_init()) == NULL)
@@ -554,6 +558,14 @@ main(int    argc,
     /* Add netconf yang spec, used by netconf client and as internal protocol */
     if (netconf_module_load(h) < 0)
 	goto done;
+    /* Here all modules are loaded 
+     * Compute and set canonical namespace context
+     */
+    if (xml_nsctx_yangspec(yspec, &nsctx_global) < 0)
+	goto done;
+    if (clicon_nsctx_global_set(h, nsctx_global) < 0)
+	goto done;
+
     /* Call start function is all plugins before we go interactive */
     if (clixon_plugin_start(h) < 0)
 	goto done;
diff --git a/apps/restconf/restconf_lib.c b/apps/restconf/restconf_lib.c
index fe8a2544..22d474cb 100644
--- a/apps/restconf/restconf_lib.c
+++ b/apps/restconf/restconf_lib.c
@@ -593,6 +593,7 @@ int
 restconf_terminate(clicon_handle h)
 {
     yang_stmt *yspec;
+    cvec      *nsctx;
     cxobj     *x;
     int        fs; /* fgcx socket */
 
@@ -606,6 +607,8 @@ restconf_terminate(clicon_handle h)
 	yspec_free(yspec);
     if ((yspec = clicon_config_yang(h)) != NULL)
 	yspec_free(yspec);
+    if ((nsctx = clicon_nsctx_global_get(h)) != NULL)
+	cvec_free(nsctx);
     if ((x = clicon_conf_xml(h)) != NULL)
 	xml_free(x);
     clicon_handle_exit(h);
diff --git a/apps/restconf/restconf_main.c b/apps/restconf/restconf_main.c
index 1bcadbfd..d7c6dc48 100644
--- a/apps/restconf/restconf_main.c
+++ b/apps/restconf/restconf_main.c
@@ -589,6 +589,7 @@ main(int    argc,
     char          *str;
     clixon_plugin *cp = NULL;
     uint32_t       id = 0;
+    cvec          *nsctx_global = NULL; /* Global namespace context */
     
     /* In the startup, logs to stderr & debug flag set later */
     clicon_log_init(__PROGRAM__, LOG_INFO, logdst); 
@@ -760,6 +761,14 @@ main(int    argc,
 	 yang_spec_parse_module(h, "clixon-rfc5277", NULL, yspec)< 0)
 	 goto done;
 
+     /* Here all modules are loaded 
+      * Compute and set canonical namespace context
+      */
+     if (xml_nsctx_yangspec(yspec, &nsctx_global) < 0)
+	 goto done;
+     if (clicon_nsctx_global_set(h, nsctx_global) < 0)
+	 goto done;
+
      /* Dump configuration options on debug */
     if (debug)      
 	clicon_option_dump(h, debug);
diff --git a/lib/clixon/clixon_data.h b/lib/clixon/clixon_data.h
index 7dfd556a..b1b61926 100644
--- a/lib/clixon/clixon_data.h
+++ b/lib/clixon/clixon_data.h
@@ -61,6 +61,9 @@ typedef struct {
 yang_stmt * clicon_dbspec_yang(clicon_handle h);
 int clicon_dbspec_yang_set(clicon_handle h, yang_stmt *ys);
 
+cvec *clicon_nsctx_global_get(clicon_handle h);
+int clicon_nsctx_global_set(clicon_handle h, cvec *nsctx);
+
 cxobj * clicon_nacm_ext(clicon_handle h);
 int clicon_nacm_ext_set(clicon_handle h, cxobj *xn);
 
diff --git a/lib/clixon/clixon_xml_nsctx.h b/lib/clixon/clixon_xml_nsctx.h
index 3c383a85..5d6987ee 100644
--- a/lib/clixon/clixon_xml_nsctx.h
+++ b/lib/clixon/clixon_xml_nsctx.h
@@ -55,5 +55,6 @@ int     xml_nsctx_get_prefix(cvec *cvv,	char *namespace, char **prefix);
 int     xml_nsctx_add(cvec *nsc, char *prefix, char *namespace);
 int     xml_nsctx_node(cxobj *x, cvec **ncp);
 int     xml_nsctx_yang(yang_stmt *yn, cvec **ncp);
+int     xml_nsctx_yangspec(yang_stmt *yspec, cvec **ncp);
 
 #endif /* _CLIXON_XML_NSCTX_H */
diff --git a/lib/src/clixon_data.c b/lib/src/clixon_data.c
index 4f23a4f2..3e6a6298 100644
--- a/lib/src/clixon_data.c
+++ b/lib/src/clixon_data.c
@@ -75,6 +75,8 @@
 
 /*! Get YANG specification for application
  * Must use hash functions directly since they are not strings.
+ * @param[in]  h     Clicon handle
+ * @retval     yspec Yang spec
  */
 yang_stmt *
 clicon_dbspec_yang(clicon_handle h)
@@ -90,6 +92,8 @@ clicon_dbspec_yang(clicon_handle h)
 
 /*! Set yang specification for application
  * ys must be a malloced pointer
+ * @param[in]  h     Clicon handle
+ * @param[in]  yspec Yang spec
  */
 int
 clicon_dbspec_yang_set(clicon_handle h, 
@@ -105,6 +109,42 @@ clicon_dbspec_yang_set(clicon_handle h,
     return 0;
 }
 
+/*! Get Global "canonical" namespace context
+ * Canonical: use prefix and namespace specified in the yang modules.
+ * @param[in]  h     Clicon handle
+ * @retval     nsctx Namespace context (malloced)
+ */
+cvec *
+clicon_nsctx_global_get(clicon_handle h)
+{
+    clicon_hash_t  *cdat = clicon_data(h);
+    size_t          len;
+    void           *p;
+
+    if ((p = clicon_hash_value(cdat, "nsctx_global", &len)) != NULL)
+	return *(cvec **)p;
+    return NULL;
+}
+
+/*! Set global "canonical" namespace context
+ * Canonical: use prefix and namespace specified in the yang modules.
+ * @param[in]  h     Clicon handle
+ * @param[in]  nsctx Namespace context (malloced)
+ */
+int
+clicon_nsctx_global_set(clicon_handle h,
+			cvec         *nsctx)
+{
+    clicon_hash_t  *cdat = clicon_data(h);
+
+    /* It is the pointer to cvec that should be copied by hash,
+       so we send a ptr to the ptr to indicate what to copy.
+     */
+    if (clicon_hash_add(cdat, "nsctx_global", &nsctx, sizeof(nsctx)) == NULL)
+	return -1;
+    return 0;
+}
+
 /*! Get NACM (rfc 8341) XML parse tree if external not in std xml config
  * @param[in]  h    Clicon handle
  * @retval     xn   XML NACM tree, or NULL
diff --git a/lib/src/clixon_xml_nsctx.c b/lib/src/clixon_xml_nsctx.c
index e588c204..1134d000 100644
--- a/lib/src/clixon_xml_nsctx.c
+++ b/lib/src/clixon_xml_nsctx.c
@@ -182,7 +182,6 @@ xml_nsctx_add(cvec  *cvv,
     return retval;
 }
 
-
 static int
 xml_nsctx_node1(cxobj *xn,
 		cvec   *nsc)
@@ -268,10 +267,10 @@ xml_nsctx_node(cxobj *xn,
     return retval;
 }
 
-/*! Create and initialize XML namespace from Yang node
+/*! Create and initialize XML namespace context from Yang node
  * Primary use is Yang path statements, eg leafrefs and others
  * Fully explore all prefix:namespace pairs from context of one node
- * @param[in]  xn     XML node
+ * @param[in]  yn     Yang statement in module tree (or module itself)
  * @param[out] ncp    XML namespace context
  * @retval     0      OK
  * @retval     -1     Error
@@ -354,3 +353,44 @@ xml_nsctx_yang(yang_stmt *yn,
     return retval;
 }
 
+/*! Create and initialize XML namespace context from Yang spec
+ *
+ * That is, create a "canonical" XML namespace mapping from all loaded yang 
+ * modules which are children of the yang specification.
+ * ALso add netconf base namespace: nc , urn:ietf:params:xml:ns:netconf:base:1.0
+ * Fully explore all prefix:namespace pairs of all yang modules
+ * @param[in]  yspec  Yang spec
+ * @param[out] ncp    XML namespace context
+ */
+int
+xml_nsctx_yangspec(yang_stmt *yspec,
+		   cvec     **ncp)
+{
+    int        retval = -1;
+    cvec      *nc = NULL;
+    yang_stmt *ymod = NULL;
+    yang_stmt *yprefix;
+    yang_stmt *ynamespace;
+
+    if ((nc = cvec_new(0)) == NULL){
+	clicon_err(OE_XML, errno, "cvec_new");
+	goto done;
+    }
+    ymod = NULL;
+    while ((ymod = yn_each(yspec, ymod)) != NULL){
+	if (yang_keyword_get(ymod) != Y_MODULE)
+	    continue;
+	if ((yprefix = yang_find(ymod, Y_PREFIX, NULL)) == NULL)
+	    continue;
+	if ((ynamespace = yang_find(ymod, Y_NAMESPACE, NULL)) == NULL)
+	    continue;
+	if (xml_nsctx_add(nc, yang_argument_get(yprefix), yang_argument_get(ynamespace)) < 0)
+	    goto done;
+    }
+    if (xml_nsctx_add(nc,  NETCONF_BASE_PREFIX, NETCONF_BASE_NAMESPACE) < 0)
+	goto done;
+    *ncp = nc;
+    retval = 0;
+ done:
+    return retval;
+}
diff --git a/lib/src/clixon_yang.c b/lib/src/clixon_yang.c
index 051627d7..6168f791 100644
--- a/lib/src/clixon_yang.c
+++ b/lib/src/clixon_yang.c
@@ -766,7 +766,7 @@ yang_find_myprefix(yang_stmt *ys)
     }
     if ((yprefix = yang_find(ymod, Y_PREFIX, NULL)) == NULL)
 	goto done;
-    prefix = yprefix->ys_argument;
+    prefix = yang_argument_get(yprefix);
  done:
     return prefix;
 }