diff --git a/src/GamCommands.txt b/src/GamCommands.txt
index 35a0accd..9970bf22 100644
--- a/src/GamCommands.txt
+++ b/src/GamCommands.txt
@@ -531,6 +531,7 @@ gam update group <GroupItem> sync [owner|manager|member] <UserTypeEntity>
 gam update group <GroupItem> update [owner|manager|member] <UserTypeEntity>
 gam delete group <GroupItem>
 gam info group <GroupItem> [nousers] [noaliases] [groups]
+gam update group <GroupItem> clear [owner] [manager] [member]
 
 gam print groups [todrive] ([domain <DomainName>] [member <UserItem>])
 	[maxresults <Number>] [delimiter <String>]
diff --git a/src/gam.py b/src/gam.py
index c838e83a..85d6daf1 100755
--- a/src/gam.py
+++ b/src/gam.py
@@ -6181,12 +6181,13 @@ def doRemoveUsersGroups(users):
 def doUpdateGroup():
   cd = buildGAPIObject(u'directory')
   group = sys.argv[3]
-  if sys.argv[4].lower() in [u'add', u'update', u'sync', u'remove']:
+  myarg = sys.argv[4].lower()
+  if myarg in [u'add', u'update', u'sync', u'remove', u'clear']:
     if group[0:3].lower() == u'uid:':
       group = group[4:]
     elif group.find(u'@') == -1:
       group = u'%s@%s' % (group, GC_Values[GC_DOMAIN])
-    if sys.argv[4].lower() in [u'add', u'update']:
+    if myarg in [u'add', u'update']:
       role = sys.argv[5].upper()
       i = 6
       if role not in [u'OWNER', u'MANAGER', u'MEMBER']:
@@ -6200,16 +6201,16 @@ def doUpdateGroup():
       for user_email in users_email:
         if user_email != u'*' and user_email.find(u'@') == -1:
           user_email = u'%s@%s' % (user_email, GC_Values[GC_DOMAIN])
-        sys.stderr.write(u' %sing %s %s...\n' % (sys.argv[4].lower(), role.lower(), user_email))
+        sys.stderr.write(u' %sing %s %s...\n' % (myarg, role.lower(), user_email))
         try:
-          if sys.argv[4].lower() == u'add':
+          if myarg == u'add':
             body = {u'role': role, u'email': user_email}
             callGAPI(cd.members(), u'insert', soft_errors=True, groupKey=group, body=body)
-          elif sys.argv[4].lower() == u'update':
+          else:
             callGAPI(cd.members(), u'update', soft_errors=True, groupKey=group, memberKey=user_email, body=body)
         except googleapiclient.errors.HttpError:
           pass
-    elif sys.argv[4].lower() == u'sync':
+    elif myarg == u'sync':
       role = sys.argv[5].upper()
       i = 6
       if role not in [u'OWNER', u'MANAGER', u'MEMBER']:
@@ -6228,7 +6229,7 @@ def doUpdateGroup():
       for user_email in to_remove:
         items.append([u'update', u'group', group, u'remove', user_email])
       run_batch(items)
-    elif sys.argv[4].lower() == u'remove':
+    elif myarg == u'remove':
       i = 5
       if sys.argv[i].lower() in [u'member', u'manager', u'owner']:
         i += 1
@@ -6243,6 +6244,25 @@ def doUpdateGroup():
           user_email = u'%s@%s' % (user_email, GC_Values[GC_DOMAIN])
         sys.stderr.write(u' removing %s\n' % user_email)
         callGAPI(cd.members(), u'delete', soft_errors=True, groupKey=group, memberKey=user_email)
+    else: # clear
+      roles = []
+      i = 5
+      while i < len(sys.argv):
+        role = sys.argv[i].upper()
+        if role in [u'OWNER', u'MANAGER', u'MEMBER']:
+          roles.append(role)
+          i += 1
+        else:
+          print u'ERROR: %s is not a valid argument for "gam update group clear"' % sys.argv[i]
+          sys.exit(2)
+      if roles:
+        roles = u','.join(sorted(set(roles)))
+      else:
+        roles = u'MEMBER'
+      user_emails = getUsersToModify(entity_type=u'group', entity=group, member_type=roles)
+      for user_email in user_emails:
+        sys.stderr.write(u' removing %s\n' % user_email)
+        callGAPI(cd.members(), u'delete', soft_errors=True, groupKey=group, memberKey=user_email)
   else:
     i = 4
     use_cd_api = False
diff --git a/src/whatsnew.txt b/src/whatsnew.txt
index fa02420c..98bbeeb9 100644
--- a/src/whatsnew.txt
+++ b/src/whatsnew.txt
@@ -15,6 +15,7 @@ GAM 3.66
   -Add domain <DomainName> and member <EmailAddress> arguments to gam print group-members to allow selecting subsets of groups
   -Add showcounts argument to gam <Users> show labels to allow seeing message counts for each label
   -Add arguments to gam <Users> show fileinfo <DriveFileId> <DriveFieldName>* to allow field selection
+  -Add option to gam update group to allow clearing members: gam update group <GroupItem> clear [owner] [manager] [member]
 
 GAM 3.65
   -fix vacation issues (Ross)