diff --git a/Supporters/lib/Supporters.pm b/Supporters/lib/Supporters.pm
index e4e499e..8e0b845 100644
--- a/Supporters/lib/Supporters.pm
+++ b/Supporters/lib/Supporters.pm
@@ -200,28 +200,37 @@ sub addEmailAddress($$$$) {
   die "addEmailAddress: invalid email address, $emailAddressType"
     unless defined $emailAddressType and Mail::RFC822::Address::valid($emailAddress);
 
+  my $existingEmail = $self->_lookupEmailAddress($emailAddress);
+  die "addEmailAddress: attempt to add email address that exists, using a different type!"
+    if defined $existingEmail and $existingEmail->{type} ne $emailAddressType;
+
+  my($sth, $addressId);
+
   $self->_beginWork();
 
-  my $addressTypeId;
-  eval {
-    $addressTypeId = $self->addAddressType($emailAddressType);
-  };
-  if ($@ or not defined $addressTypeId) {
-    my $err = $@;
-    $err = "addEmailAddress: unable to addAddressType"  if (not defined $err);
-    $self->_rollback();
-    die $@ if $@;
+  if (defined $existingEmail) {
+    $addressId = $existingEmail->{id};
+  } else {
+    my $addressTypeId;
+    eval {
+      $addressTypeId = $self->addAddressType($emailAddressType);
+    };
+    if ($@ or not defined $addressTypeId) {
+      my $err = $@;
+      $err = "addEmailAddress: unable to addAddressType"  if (not defined $err);
+      $self->_rollback();
+      die $@ if $@;
+    }
+    $sth = $self->dbh->prepare("INSERT INTO email_address(email_address, type_id, date_encountered)" .
+                                  "VALUES(                    ?,            ?,       date('now'))");
+
+    $sth->execute($emailAddress, $addressTypeId);
+    $addressId = $self->dbh->last_insert_id("","","","");
+    $sth->finish();
   }
-  my $sth = $self->dbh->prepare("INSERT INTO email_address(email_address, type_id, date_encountered)" .
-                                "VALUES(                    ?,            ?,       date('now'))");
-
-  $sth->execute($emailAddress, $addressTypeId);
-  my $addressId = $self->dbh->last_insert_id("","","","");
-  $sth->finish();
-
   $sth = $self->dbh->prepare("INSERT INTO donor_email_address_mapping" .
-                                      "(donor_id, email_address_id) " .
-                                "VALUES(       ?, ?)");
+                             "(donor_id, email_address_id) " .
+                             "VALUES(       ?, ?)");
   $sth->execute($id, $addressId);
   $sth->finish();
 
diff --git a/Supporters/t/Supporters.t b/Supporters/t/Supporters.t
index 104e6e0..54addc7 100644
--- a/Supporters/t/Supporters.t
+++ b/Supporters/t/Supporters.t
@@ -5,7 +5,7 @@
 use strict;
 use warnings;
 
-use Test::More tests => 176;
+use Test::More tests => 182;
 use Test::Exception;
 
 use Scalar::Util qw(looks_like_number reftype);
@@ -131,9 +131,25 @@ ok((not defined $val or not defined $val->{'name'}),
 my $drapperEmailId;
 
 lives_ok { $drapperEmailId = $sp->addEmailAddress($drapperId, 'drapper@example.org', 'work') }
-         "addEmailAdress: inserting a valid email address works";
+         "addEmailAddress: inserting a valid email address works";
 ok((looks_like_number($drapperEmailId) and $drapperEmailId > 0), "addEmailAddress: id returned is sane.");
 
+my $olsonEmailId2;
+
+dies_ok { $olsonEmailId2 = $sp->addEmailAddress($olsonId, 'drapper@example.org', 'paypal') }
+         "addEmailAddress: fails when adding the same email address for someone else, but as a different type";
+
+my $drapperEmailId2;
+lives_ok { $drapperEmailId2 = $sp->addEmailAddress($drapperId, 'everyone@example.net', 'paypal') }
+         "addEmailAddress: inserting a second valid email address works";
+ok((looks_like_number($drapperEmailId2) and $drapperEmailId2 > 0 and $drapperEmailId != $drapperEmailId2),
+   "addEmailAddress: id returned is sane and is not same as previous id.");
+
+lives_ok { $olsonEmailId2 = $sp->addEmailAddress($olsonId, 'everyone@example.net', 'paypal') }
+         "addEmailAddress: binding known email address to another person works...";
+ok((looks_like_number($olsonEmailId2) and $olsonEmailId2 > 0 and $olsonEmailId2 == $drapperEmailId2),
+   "addEmailAddress: ... and id returned is sane and is same.");
+
 =item addAddressType
 
 =cut
@@ -546,7 +562,11 @@ dies_ok { $sp->_lookupEmailAddress(undef); } "_lookupEmailAddressId: dies for un
 
 is_deeply($sp->_lookupEmailAddress('drapper@example.org'),
           { emailAddress => 'drapper@example.org', id => $drapperEmailId, type => 'work', dateEncountered => $today },
-    "_lookupEmailAddressId: returns email Id for known item");
+    "_lookupEmailAddressId: 1 returns email Id for known item");
+
+is_deeply($sp->_lookupEmailAddress('everyone@example.net'),
+          { emailAddress => 'everyone@example.net', id => $olsonEmailId2, type => 'paypal', dateEncountered => $today },
+    "_lookupEmailAddressId: 2 returns email id for known item");
 
 is($sp->_lookupEmailAddress('drapper@example.com'), undef,
     "_lookupEmailAddressId: returns undef for unknown item.");