diff --git a/focker.py b/focker.py
index a97a760..68a8c32 100644
--- a/focker.py
+++ b/focker.py
@@ -2,7 +2,8 @@ from argparse import ArgumentParser
 import yaml
 import os
 # from weir import zfs, process
-from .image import command_image_build
+from .image import command_image_build, \
+    command_image_untag
 import sys
 from .zfs import zfs_init
 
@@ -17,6 +18,10 @@ def create_parser():
     parser.add_argument('focker_dir', type=str)
     parser.add_argument('--tag', '-t', type=str, nargs='+', default=[])
 
+    parser = subparsers.add_parser('untag')
+    parser.set_defaults(func=command_image_untag)
+    parser.add_argument('tags', type=str, nargs='+', default=[])
+
     return parser_top
 
 
diff --git a/image.py b/image.py
index 2bb2c1c..7eeb4b3 100644
--- a/image.py
+++ b/image.py
@@ -70,3 +70,6 @@ def command_image_build(args):
     image, image_sha256 = build(spec)
     zfs_untag(args.tag)
     zfs_tag(image.split('@')[0], args.tag)
+
+def command_image_untag(args):
+    zfs_untag(args.tags)
diff --git a/zfs.py b/zfs.py
index f459072..0e38deb 100644
--- a/zfs.py
+++ b/zfs.py
@@ -72,11 +72,12 @@ def zfs_snapshot_by_sha256(sha256):
     return lst[0][1]
 
 
-def zfs_tag(name, tags):
+def zfs_tag(name, tags, replace=False):
     lst = zfs_parse_output(['zfs', 'list', '-o', 'focker:tags', '-H', name])
-    tags = list(tags)
-    tags.extend(lst[0][0].split(' '))
-    tags = list(set(tags))
+    if not replace:
+        tags = list(tags)
+        tags.extend(lst[0][0].split(' '))
+        tags = list(set(tags))
     if len(tags) > 0:
         zfs_run(['zfs', 'set', 'focker:tags=' + ' '.join(tags), name])
     else:
@@ -84,6 +85,7 @@ def zfs_tag(name, tags):
 
 
 def zfs_untag(tags):
+    # print('zfs_untag(), tags:', tags)
     lst = zfs_parse_output(['zfs', 'list', '-o', 'name,focker:tags', '-H'])
     lst = filter(lambda a: any([b in a[1].split(' ') for b in tags]), lst)
     for row in lst:
@@ -91,7 +93,7 @@ def zfs_untag(tags):
         for t in tags:
             if t in cur_tags:
                 cur_tags.remove(t)
-        zfs_tag(row[0], cur_tags)
+        zfs_tag(row[0], cur_tags, replace=True)
 
 
 def zfs_init():