diff --git a/orte/mca/odls/base/odls_base_default_fns.c b/orte/mca/odls/base/odls_base_default_fns.c
index becb83250c..405d5fc3aa 100644
--- a/orte/mca/odls/base/odls_base_default_fns.c
+++ b/orte/mca/odls/base/odls_base_default_fns.c
@@ -81,6 +81,8 @@
 #include "orte/mca/odls/base/base.h"
 #include "orte/mca/odls/base/odls_private.h"
 
+static bool override_oversubscribed = false;
+
 /* IT IS CRITICAL THAT ANY CHANGE IN THE ORDER OF THE INFO PACKED IN
  * THIS FUNCTION BE REFLECTED IN THE CONSTRUCT_CHILD_LIST PARSER BELOW
 */
@@ -346,6 +348,12 @@ int orte_odls_base_default_get_add_procs_data(opal_buffer_t *data,
         return rc;
     }
     
+    /* pack the oversubscribe override flag */
+    if (ORTE_SUCCESS != (rc = opal_dss.pack(data, &jdata->oversubscribe_override, 1, OPAL_BOOL))) {
+        ORTE_ERROR_LOG(rc);
+        return rc;
+    }
+
     /* pack the map & binding policy for this job */
     if (ORTE_SUCCESS != (rc = opal_dss.pack(data, &map->policy, 1, ORTE_MAPPING_POLICY))) {
         ORTE_ERROR_LOG(rc);
@@ -804,6 +812,12 @@ int orte_odls_base_default_construct_child_list(opal_buffer_t *data,
         ORTE_ERROR_LOG(rc);
         goto REPORT_ERROR;
     }
+    /* unpack the override oversubscribed flag */
+    cnt=1;
+    if (ORTE_SUCCESS != (rc = opal_dss.unpack(data, &override_oversubscribed, &cnt, OPAL_BOOL))) {
+        ORTE_ERROR_LOG(rc);
+        goto REPORT_ERROR;
+    }
     /* unpack the mapping policy for the job */
     cnt=1;
     if (ORTE_SUCCESS != (rc = opal_dss.unpack(data, &jobdat->policy, &cnt, ORTE_MAPPING_POLICY))) {
@@ -1426,20 +1440,6 @@ int orte_odls_base_default_launch_local(orte_jobid_t job,
      */
     getcwd(basedir, sizeof(basedir));
 
-    /* compute the number of local procs alive or about to be launched
-     * as part of this job
-     */
-    num_procs_alive = 0;
-    for (item = opal_list_get_first(&orte_local_children);
-         item != opal_list_get_end(&orte_local_children);
-         item = opal_list_get_next(item)) {
-        child = (orte_odls_child_t*)item;
-        if (child->alive ||
-            OPAL_EQUAL == opal_dss.compare(&job, &(child->name->jobid), ORTE_JOBID)) {
-            num_procs_alive++;
-        }
-    }
-    
     /* find the jobdat for this job */
     jobdat = NULL;
     for (item = opal_list_get_first(&orte_local_jobdata);
@@ -1521,8 +1521,10 @@ int orte_odls_base_default_launch_local(orte_jobid_t job,
     orte_sstore.wait_all_deps();
 #endif
 
-    /* if the mapper says we are oversubscribed, then we trust it */
-    if (oversubscribed) {
+    /* if the mapper says we are oversubscribed, then we trust it - unless
+     * it told us -not- to!
+     */
+    if (oversubscribed && !override_oversubscribed) {
         OPAL_OUTPUT_VERBOSE((5, orte_odls_globals.output,
                              "%s odls:launch mapper declares this node oversubscribed",
                              ORTE_NAME_PRINT(ORTE_PROC_MY_NAME)));
@@ -1532,6 +1534,20 @@ int orte_odls_base_default_launch_local(orte_jobid_t job,
          * is done solely in case the mapper had incorrect knowledge of
          * the #local processors
          */
+        /* compute the number of local procs alive or about to be launched
+         * as part of this job
+         */
+        num_procs_alive = 0;
+        for (item = opal_list_get_first(&orte_local_children);
+             item != opal_list_get_end(&orte_local_children);
+             item = opal_list_get_next(item)) {
+            child = (orte_odls_child_t*)item;
+            if (child->alive ||
+                OPAL_EQUAL == opal_dss.compare(&job, &(child->name->jobid), ORTE_JOBID)) {
+                num_procs_alive++;
+            }
+        }
+        /* get the number of local processors */
         if (ORTE_SUCCESS != (rc = opal_paffinity_base_get_processor_info(&num_processors))) {
             /* if we cannot find the number of local processors, we have no choice
              * but to default to conservative settings
@@ -1550,7 +1566,7 @@ int orte_odls_base_default_launch_local(orte_jobid_t job,
             }
         }
         OPAL_OUTPUT_VERBOSE((5, orte_odls_globals.output,
-                             "%s odls:launch found %d processors for %d children and set oversubscribed to %s",
+                             "%s odls:launch found %d processors for %d children and locally set oversubscribed to %s",
                              ORTE_NAME_PRINT(ORTE_PROC_MY_NAME),
                              (ORTE_SUCCESS == rc) ? num_processors : -1, (int)opal_list_get_size(&orte_local_children),
                              oversubscribed ? "true" : "false"));