diff --git a/apps/mosquitto_ctrl/dynsec.c b/apps/mosquitto_ctrl/dynsec.c
index 8ecb761f..f00e0f1d 100644
--- a/apps/mosquitto_ctrl/dynsec.c
+++ b/apps/mosquitto_ctrl/dynsec.c
@@ -41,6 +41,7 @@ void dynsec__print_usage(void)
 	printf("Create a new client:         createClient      <username> [-c clientid] [-p password]\n");
 	printf("Delete a client:             deleteClient      <username>\n");
 	printf("Set a client password:       setClientPassword <username> [password]\n");
+	printf("Set a client id:             setClientId       <username> [clientid]\n");
 	printf("Add a role to a client:      addClientRole     <username> <rolename> [priority]\n");
 	printf("    Higher priority (larger numerical value) roles are evaluated first.\n");
 	printf("Remove role from a client:   removeClientRole  <username> <rolename>\n");
@@ -803,6 +804,8 @@ int dynsec__main(int argc, char *argv[], struct mosq_ctrl *ctrl)
 		rc = dynsec_client__get(argc-1, &argv[1], j_command);
 	}else if(!strcasecmp(argv[0], "listClients")){
 		rc = dynsec_client__list_all(argc-1, &argv[1], j_command);
+	}else if(!strcasecmp(argv[0], "setClientId")){
+		rc = dynsec_client__set_id(argc-1, &argv[1], j_command);
 	}else if(!strcasecmp(argv[0], "setClientPassword")){
 		rc = dynsec_client__set_password(argc-1, &argv[1], j_command);
 	}else if(!strcasecmp(argv[0], "addClientRole")){
diff --git a/apps/mosquitto_ctrl/dynsec_client.c b/apps/mosquitto_ctrl/dynsec_client.c
index d6bc3a11..f007b3da 100644
--- a/apps/mosquitto_ctrl/dynsec_client.c
+++ b/apps/mosquitto_ctrl/dynsec_client.c
@@ -117,6 +117,30 @@ int dynsec_client__enable_disable(int argc, char *argv[], cJSON *j_command, cons
 	}
 }
 
+int dynsec_client__set_id(int argc, char *argv[], cJSON *j_command)
+{
+	char *username = NULL, *clientid = NULL;
+
+	if(argc == 2){
+		username = argv[0];
+		clientid = argv[1];
+	}else if(argc == 1){
+		username = argv[0];
+	}else{
+		return MOSQ_ERR_INVAL;
+	}
+
+	if(cJSON_AddStringToObject(j_command, "command", "setClientId") == NULL
+			|| cJSON_AddStringToObject(j_command, "username", username) == NULL
+			|| (clientid && cJSON_AddStringToObject(j_command, "clientid", clientid) == NULL)
+			){
+
+		return MOSQ_ERR_NOMEM;
+	}else{
+		return MOSQ_ERR_SUCCESS;
+	}
+}
+
 int dynsec_client__set_password(int argc, char *argv[], cJSON *j_command)
 {
 	char *username = NULL, *password = NULL;
diff --git a/apps/mosquitto_ctrl/mosquitto_ctrl.h b/apps/mosquitto_ctrl/mosquitto_ctrl.h
index 248b8401..a51af2c3 100644
--- a/apps/mosquitto_ctrl/mosquitto_ctrl.h
+++ b/apps/mosquitto_ctrl/mosquitto_ctrl.h
@@ -95,6 +95,7 @@ int dynsec_client__delete(int argc, char *argv[], cJSON *j_command);
 int dynsec_client__enable_disable(int argc, char *argv[], cJSON *j_command, const char *command);
 int dynsec_client__get(int argc, char *argv[], cJSON *j_command);
 int dynsec_client__list_all(int argc, char *argv[], cJSON *j_command);
+int dynsec_client__set_id(int argc, char *argv[], cJSON *j_command);
 int dynsec_client__set_password(int argc, char *argv[], cJSON *j_command);
 
 int dynsec_group__add_remove_client(int argc, char *argv[], cJSON *j_command, const char *command);
diff --git a/plugins/dynamic-security/clients.c b/plugins/dynamic-security/clients.c
index 9c04b1bf..d4841231 100644
--- a/plugins/dynamic-security/clients.c
+++ b/plugins/dynamic-security/clients.c
@@ -546,6 +546,52 @@ int dynsec_clients__process_enable(cJSON *j_responses, struct mosquitto *context
 }
 
 
+int dynsec_clients__process_set_id(cJSON *j_responses, struct mosquitto *context, cJSON *command, char *correlation_data)
+{
+	char *username, *clientid, *clientid_heap;
+	struct dynsec__client *client;
+
+	if(json_get_string(command, "username", &username, false) != MOSQ_ERR_SUCCESS){
+		dynsec__command_reply(j_responses, context, "setClientId", "Invalid/missing username", correlation_data);
+		return MOSQ_ERR_INVAL;
+	}
+	if(mosquitto_validate_utf8(username, (int)strlen(username)) != MOSQ_ERR_SUCCESS){
+		dynsec__command_reply(j_responses, context, "setClientId", "Username not valid UTF-8", correlation_data);
+		return MOSQ_ERR_INVAL;
+	}
+
+	if(json_get_string(command, "clientid", &clientid, false) != MOSQ_ERR_SUCCESS){
+		dynsec__command_reply(j_responses, context, "setClientId", "Invalid/missing client ID", correlation_data);
+		return MOSQ_ERR_INVAL;
+	}
+	if(mosquitto_validate_utf8(clientid, (int)strlen(clientid)) != MOSQ_ERR_SUCCESS){
+		dynsec__command_reply(j_responses, context, "setClientId", "Client ID not valid UTF-8", correlation_data);
+		return MOSQ_ERR_INVAL;
+	}
+
+	client = dynsec_clients__find(username);
+	if(client == NULL){
+		dynsec__command_reply(j_responses, context, "setClientId", "Client not found", correlation_data);
+		return MOSQ_ERR_SUCCESS;
+	}
+
+	clientid_heap = mosquitto_strdup(clientid);
+	if(clientid_heap == NULL){
+		dynsec__command_reply(j_responses, context, "setClientId", "Internal error", correlation_data);
+		return MOSQ_ERR_NOMEM;
+	}
+	if(client->clientid){
+		mosquitto_free(client->clientid);
+	}
+	client->clientid = clientid_heap;
+
+	/* Enforce any changes */
+	mosquitto_kick_client_by_username(username, false);
+
+	return MOSQ_ERR_SUCCESS;
+}
+
+
 int dynsec_clients__process_set_password(cJSON *j_responses, struct mosquitto *context, cJSON *command, char *correlation_data)
 {
 	char *username, *password;
diff --git a/plugins/dynamic-security/dynamic_security.h b/plugins/dynamic-security/dynamic_security.h
index 8ddcc893..f46e437d 100644
--- a/plugins/dynamic-security/dynamic_security.h
+++ b/plugins/dynamic-security/dynamic_security.h
@@ -182,6 +182,7 @@ int dynsec_clients__process_get(cJSON *j_responses, struct mosquitto *context, c
 int dynsec_clients__process_list(cJSON *j_responses, struct mosquitto *context, cJSON *command, char *correlation_data);
 int dynsec_clients__process_modify(cJSON *j_responses, struct mosquitto *context, cJSON *command, char *correlation_data);
 int dynsec_clients__process_remove_role(cJSON *j_responses, struct mosquitto *context, cJSON *command, char *correlation_data);
+int dynsec_clients__process_set_id(cJSON *j_responses, struct mosquitto *context, cJSON *command, char *correlation_data);
 int dynsec_clients__process_set_password(cJSON *j_responses, struct mosquitto *context, cJSON *command, char *correlation_data);
 struct dynsec__client *dynsec_clients__find(const char *username);
 
diff --git a/plugins/dynamic-security/plugin.c b/plugins/dynamic-security/plugin.c
index 837f15d2..264fef35 100644
--- a/plugins/dynamic-security/plugin.c
+++ b/plugins/dynamic-security/plugin.c
@@ -539,6 +539,8 @@ int dynsec__handle_control(cJSON *j_responses, struct mosquitto *context, cJSON
 					rc = dynsec_clients__process_modify(j_responses, context, aiter, correlation_data);
 				}else if(!strcasecmp(command, "setClientPassword")){
 					rc = dynsec_clients__process_set_password(j_responses, context, aiter, correlation_data);
+				}else if(!strcasecmp(command, "setClientId")){
+					rc = dynsec_clients__process_set_id(j_responses, context, aiter, correlation_data);
 				}else if(!strcasecmp(command, "addClientRole")){
 					rc = dynsec_clients__process_add_role(j_responses, context, aiter, correlation_data);
 				}else if(!strcasecmp(command, "removeClientRole")){