diff --git a/lib/RT/Extension/Assets/Import/CSV.pm b/lib/RT/Extension/Assets/Import/CSV.pm
index 29e3b04..fae77f9 100644
--- a/lib/RT/Extension/Assets/Import/CSV.pm
+++ b/lib/RT/Extension/Assets/Import/CSV.pm
@@ -58,7 +58,7 @@ sub run {
                     "Missing custom field $cfname for "._column($field2csv->{$fieldname}).", skipping");
                 delete $field2csv->{$fieldname};
             }
-        } elsif ($fieldname =~ /^(id|Name|Status|Description|Catalog|Created|LastUpdated)$/) {
+        } elsif ($fieldname =~ /^(id|Name|Status|Description|Catalog|Catalogue|Created|LastUpdated)$/) {
             # no-op, these are fine
         } elsif ( RT::Asset->HasRole($fieldname) ) {
             # no-op, roles are fine
@@ -165,26 +165,21 @@ sub run {
                         RT->Logger->error("Failed to set CF $cfname to $value for row $i: $msg");
                     }
                 } elsif ($asset->HasRole($field)) {
-                    my $user = RT::User->new( $args{CurrentUser} );
-                    $user->Load( $value );
-                    $user = RT->Nobody unless $user->id;
-                    next if $asset->RoleGroup($field)->HasMember( $user->PrincipalId );
 
-                    $changes++;
-                    my ($ok, $msg) = $asset->AddRoleMember( PrincipalId => $user->PrincipalId, Type => $field );
-                    unless ($ok) {
-                        RT->Logger->error("Failed to set $field to $value for row $i: $msg");
-                    }
+                    # Manage roles linkg to principals.
+                    process_roles_field(\%args, $asset, $i, $field, $value, \$changes);
                 } else {
-                    if ($field eq "Catalog") {
+                    my $method = $field;
+                    if ($field =~ "Catalog(ue)?") {
                         my $catalog = RT::Catalog->new( $args{CurrentUser} );
                         $catalog->Load( $value );
                         $value = $catalog->id;
+                        $method = 'Catalog';
                     }
 
-                    if ($asset->$field ne $value) {
+                    if ($asset->$method ne $value) {
                         $changes++;
-                        my $method = "Set" . $field;
+                        $method = "Set" . $method;
                         my ($ok, $msg) = $asset->$method( $value );
                         unless ($ok) {
                             RT->Logger->error("Failed to set $field to $value for row $i: $msg");
@@ -310,6 +305,158 @@ sub parse_csv {
     return @items;
 }
 
+sub process_roles_field {
+    my $args    = shift;
+    my $asset   = shift;
+    my $i       = shift;
+    my $field   = shift;
+    my $value   = shift;
+    my $changes = shift;
+
+    my $user = RT::User->new( $args->{CurrentUser} );
+    my $group;
+
+    # Ooof, RT::Asset uses "Owner" and "HeldBy" for those, but for "Contact"
+    # it uses "Contacts". We need to handle that.
+    my $method = ($field eq 'Contact' ? 'Contacts' : $field);
+
+    # Find all the existing principals so we can delete any not present in
+    # the CSV. Assume all should be removed, unless we find them. We split
+    # out users and groups to allow us to use nicer log lines later on.
+    my %existing_principals;
+
+    if ($field eq 'Owner' && RT->Config->Get('AssetMultipleOwner') == 0) {
+       # By default Owner can only be a single user or group. And
+       # $asset->Owner will return that user or group.
+       $existing_principals{user}{$asset->Owner->id} = 0;
+
+    } else {
+        my $principals;
+
+        # Find users.
+        if ($field eq 'Owner') {
+            # The Owner method in RT::Asset only ever returns the first
+            # principal. We need to use RoleGroup to get them all.
+            $principals = $asset->RoleGroup('Owner')->MembersObj;
+        } else {
+            $principals = $asset->$method->MembersObj;
+        }
+
+        # We're dealing with users here.
+        $principals->LimitToUsers;
+        while (my $principal = $principals->Next) {
+            $existing_principals{user}{$principal->MemberId} = 0;
+        }
+
+        # Find groups. We need to repeat creating the principals
+        # object because LimitToGroups doesn't undo the previous
+        # LimitToUsers call.
+        if ($field eq 'Owner') {
+            # The Owner method in RT::Asset only ever returns the first
+            # principal. We need to use RoleGroup to get them all.
+            $principals = $asset->RoleGroup('Owner')->MembersObj;
+        } else {
+            $principals = $asset->$method->MembersObj;
+        }
+
+        # We're dealing with groups here.
+        $principals->LimitToGroups;
+
+        while (my $principal = $principals->Next) {
+            $existing_principals{group}{$principal->MemberId} = 0;
+        }
+    }
+
+    # Strip out anything in brackets as that is the fullname of the user.
+    $value =~ s/\s+\(.*?\)//g;
+
+    # Usernames can have commas in them (huh? yes, try it), so we need to
+    # split on ", ". Turns out they can also have spaces. People that put
+    # ", " in a username get to keep the pieces.
+    my $count = 0;
+    for my $name (split(/,\s/, $value)) {
+        $name =~ s/\+$//;
+        $count++;
+
+        if ($field eq 'Owner' && RT->Config->Get('AssetMultipleOwner') == 0
+            && $count > 1) {
+            RT->Logger->error("You're trying to set more than one Owner for row $i, but AssetMultipleOwner is off, skipping extra(s)");
+        }
+
+        # I expect that users will be more common then groups, make 'em the
+        # default.
+        my $type      = 'user';
+        my $principal = $user;
+
+        if ($name =~ /^[Gg]roup: ?(.*)$/) {
+            # Add a group.
+            #
+            # Lazy create a group for lookups.
+            $group ||= RT::Group->new( $args->{CurrentUser} );
+
+            $name = $1;  # Keep this for log lines.
+            $group->LoadUserDefinedGroup($name);
+
+            $type      = 'group';
+            $principal = $group;
+        } else {
+            # Add a user.
+
+            # Is it safe to assume the Nobody account always starts with
+            # Nobody?
+            if ($name =~ /^Nobody/) {
+                $principal = RT->Nobody;
+            } else {
+                $principal->Load( $name );
+            }
+        }
+
+        if (! $principal->id ) {
+            RT->Logger->error("Unable to find $type $name in $field for row $i, skipping");
+            next;
+        }
+
+        my $id = $principal->PrincipalId;
+
+        # We don't need to remove this principal from the role.
+        delete $existing_principals{$type}{$id};
+
+        # Already a member, our job with this principal is done.
+        next if $asset->RoleGroup($field)->HasMember( $id );
+
+        my ($ok, $msg) = $asset->AddRoleMember( PrincipalId => $id, Type => $field );
+        if ($ok) {
+            RT->Logger->info("Added $type $id to $field for row $i (asset " . $asset->id . ")");
+            $$changes++;
+
+            if ($field eq 'Owner' && RT->Config->Get('AssetMultipleOwner') == 0) {
+                # If this is an Owner, and AssetMultipleOwner is off, then
+                # setting a new Owner will remove the old Owner. We'll
+                # forget about removing any surplus users or groups as there
+                # is nothing to remove, and we'd get bogus error messages
+                # in the clean up stage..
+                delete $existing_principals{$type};
+            }
+        } else {
+            RT->Logger->error("Failed to add $type " . $principal->Name . " in $field for row $i: $msg");
+        }
+    }
+
+    # Delete any principals that should no longer be in this role.
+    for my $type (qw/group user/) {
+        for my $id (keys %{ $existing_principals{$type} }) {
+            my ($ok, $msg) = $asset->DeleteRoleMember( PrincipalId => $id, Type => $field);
+
+            if ($ok && $msg =~ /Member deleted/) {
+                RT->Logger->info("Deleted $type $id from $field for row $i (asset " . $asset->id . ")");
+                $$changes++;
+            } else {
+                RT->Logger->error("Failed to delete $type $id from $field for row $i (asset " . $asset->id . "): $msg");
+            }
+        }
+    }
+}
+
 =head1 NAME
 
 RT-Extension-Assets-Import-CSV - RT Assets Import from CSV
@@ -418,6 +565,20 @@ the C<%AssetsImportFieldMapping>:
 This requires that, after the import, RT becomes the generator of all
 asset ids.  Otherwise, asset id conflicts may occur.
 
+=head2 Roles
+
+You can add multiple principals to role which support that (HeldBy & Contact)
+by separating them with ", ". The space is required as commas are allowed in
+usernames within RT. If you have a username with ", " in it, then sorry, you
+can add to assets with this tool. To add a group use "group: Group name"
+
+Any users or groups in a role which aren't mentioned in the CSV will be
+removed from the asset.
+
+Roles you can use: Owner, HeldBy, Contact
+
+If AssetMultipleOwner is off (the default), then only one Owner can be set.
+
 =head1 AUTHOR
 
 Best Practical Solutions, LLC E<lt>modules@bestpractical.comE<gt>