diff --git a/README.md b/README.md
index 68f6a5e..8a757d4 100644
--- a/README.md
+++ b/README.md
@@ -177,6 +177,8 @@ optional arguments:
 usage: yimportgroups [-h] [-y {1.7,1.8,1.9}] -i INTERNAL_DOMAINS
                      [--offline-check | --online-check] [--allow-update]
                      [--delete] [--verbose] [--no-validate-domains]
+                     [--creator-user CREATOR_USER]
+                     [--creator-zone CREATOR_ZONE]
                      csvfile
 
 Creates a list of groups based on a CSV file
@@ -197,6 +199,10 @@ optional arguments:
   --verbose, -v         Show information as extracted from CSV file
   --no-validate-domains, -n
                         Do not validate email address domains
+  --creator-user CREATOR_USER
+                        User who creates user
+  --creator-zone CREATOR_ZONE
+                        Zone of the user who creates user
 
         The CSV file is expected to include the following labels in its header (the first row):
         'category'    = category for the group
diff --git a/yclienttools/common_rules.py b/yclienttools/common_rules.py
index 90719ea..92876e6 100644
--- a/yclienttools/common_rules.py
+++ b/yclienttools/common_rules.py
@@ -100,6 +100,22 @@ def call_uuGroupGetMemberType(self, groupname, user):
            ( 'user', user) ])
        return self.call_rule('uuGroupGetMemberType', parms, 1)[0]
 
+    def call_uuGroupUserAddByOtherCreator(self, groupname, username, creator_user, creator_zone):
+       """Adds user to group on the behalf of a creator user.
+
+          :param: groupname
+          :param: username
+          :param: creator_user
+          :param: creator_zone
+          :returns: (status, message) ; status !=0 is error
+       """
+       parms = OrderedDict([
+           ('groupname', groupname),
+           ('username', username),
+           ('creatorUser', creator_user),
+           ('creatorZone', creator_zone)])
+       return self.call_rule('uuGroupUserAdd', parms, 2)
+
     def call_uuGroupUserAdd(self, groupname, username):
        """Adds user to group.
 
@@ -176,9 +192,11 @@ def call_uuGroupAdd(self, groupname, category,
                ('category', category),
                ('subcategory', subcategory),
                ('schema_id', 'default-2'),
-               ('expirationdate', ''),
+               ('expiration_date', ''),
                ('description', description),
-               ('classification', classification)])
+               ('dataClassification', classification),
+               ('co_identifier', '')
+               ])
 
        return self.call_rule('uuGroupAdd', parms, 2)
 
diff --git a/yclienttools/importgroups.py b/yclienttools/importgroups.py
index 172f3d7..8a875ce 100644
--- a/yclienttools/importgroups.py
+++ b/yclienttools/importgroups.py
@@ -184,8 +184,9 @@ def validate_data(rule_interface, args, data):
         for user in managers + members + viewers:
             if not is_internal_user(user, args.internal_domains.split(",")):
                 # ensure that external users already have an iRODS account
-                # we do not want to be the actor that creates them
-                if not rule_interface.call_uuUserExists(user):
+                # we do not want to be the actor that creates them (unless
+                # we are creating them in the name of a creator user)
+                if not rule_interface.call_uuUserExists(user)and not args.creator_user:
                     errors.append(
                         'Group {} has nonexisting external user {}'.format(groupname, user))
 
@@ -222,7 +223,10 @@ def apply_data(rule_interface, args, data):
             currentrole = rule_interface.call_uuGroupGetMemberType(groupname, username)
 
             if currentrole == "none":
-                [status, msg] = rule_interface.call_uuGroupUserAdd(groupname, username)
+                if args.creator_user:
+                    [status, msg] = rule_interface.call_uuGroupUserAddByOtherCreator(groupname, username, args.creator_user, args.creator_zone)
+                else:
+                    [status, msg] = rule_interface.call_uuGroupUserAdd(groupname, username)
 
                 if status == '0':
                      currentrole = "member"
@@ -333,6 +337,9 @@ def entry():
     if args.delete and not args.allow_update:
         _exit_with_error("Using the --delete option without the --allow-update option is not supported.")
 
+    if (args.creator_user and not args.creator_zone) or (not args.creator_user and args.creator_zone):
+        _exit_with_error("Using the --creator-user option without the --creator-zone option is not supported.")
+
     if args.offline_check:
         sys.exit(0)
 
@@ -379,6 +386,10 @@ def _get_args():
                         help='Show information as extracted from CSV file')
     parser.add_argument('--no-validate-domains', '-n', action='store_true',
                         help='Do not validate email address domains')
+    parser.add_argument('--creator-user', type=str,
+                        help='User who creates user')
+    parser.add_argument('--creator-zone', type=str,
+                        help='Zone of the user who creates user')
     return parser.parse_args()