diff --git a/res/values/strings.xml b/res/values/strings.xml
index a40bce1..fbedf58 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -675,6 +675,9 @@
       and return to the editor [CHAR LIMIT=30] -->
     <string name="cancel_confirmation_dialog_keep_editing_button">Cancel</string>
 
+    <!-- Contents of the alert dialog when the user hits the Cancel button in the customize screen [CHAR LIMIT=128] -->
+    <string name="leave_customize_confirmation_dialog_message">Discard customizations?</string>
+
     <!-- Description of a call log entry, made of a call type and a date -->
     <string name="call_type_and_date">
         <xliff:g id="call_type" example="Friends">%1$s</xliff:g>  <xliff:g id="call_short_date" example="Friends">%2$s</xliff:g>
diff --git a/res/values/styles.xml b/res/values/styles.xml
index 9ff882d..33fa11e 100644
--- a/res/values/styles.xml
+++ b/res/values/styles.xml
@@ -486,11 +486,6 @@
         <item name="android:overScrollMode">always</item>
     </style>
 
-    <style name="ContactListFilterTheme" parent="@android:Theme.Holo.Light">
-        <item name="android:listViewStyle">@style/ListViewStyle</item>
-        <item name="android:actionButtonStyle">@style/FilterActionButtonStyle</item>
-    </style>
-
     <!-- Adding padding to action button doesn't move it to left, we increase the button width to
      make margin between the button and screen edge 16dp -->
     <style name="FilterActionButtonStyle" parent="@android:Widget.ActionButton">
diff --git a/src/com/android/contacts/common/list/AccountFilterActivity.java b/src/com/android/contacts/common/list/AccountFilterActivity.java
index bed6977..3908d18 100644
--- a/src/com/android/contacts/common/list/AccountFilterActivity.java
+++ b/src/com/android/contacts/common/list/AccountFilterActivity.java
@@ -90,8 +90,9 @@
         if (filter.filterType == ContactListFilter.FILTER_TYPE_CUSTOM) {
             mCustomFilterView = listFilterView;
             mIsCustomFilterViewSelected = listFilterView.isChecked();
-            final Intent intent = new Intent(this,
-                    CustomContactListFilterActivity.class);
+            final Intent intent = new Intent(this, CustomContactListFilterActivity.class)
+                    .putExtra(CustomContactListFilterActivity.EXTRA_CURRENT_LIST_FILTER_TYPE,
+                            mCurrentFilterType);
             listFilterView.setActivated(true);
             // Switching activity has the highest priority. So when we open another activity, the
             // announcement that indicates an account is checked will be interrupted. This is the
diff --git a/src/com/android/contacts/common/list/CustomContactListFilterActivity.java b/src/com/android/contacts/common/list/CustomContactListFilterActivity.java
index 04337b8..74e8f84 100644
--- a/src/com/android/contacts/common/list/CustomContactListFilterActivity.java
+++ b/src/com/android/contacts/common/list/CustomContactListFilterActivity.java
@@ -19,6 +19,8 @@
 import android.app.ActionBar;
 import android.app.Activity;
 import android.app.AlertDialog;
+import android.app.Dialog;
+import android.app.DialogFragment;
 import android.app.LoaderManager.LoaderCallbacks;
 import android.app.ProgressDialog;
 import android.content.AsyncTaskLoader;
@@ -30,14 +32,12 @@
 import android.content.Intent;
 import android.content.Loader;
 import android.content.OperationApplicationException;
-import android.content.SharedPreferences;
 import android.database.Cursor;
 import android.graphics.Color;
 import android.graphics.drawable.ColorDrawable;
 import android.net.Uri;
 import android.os.Bundle;
 import android.os.RemoteException;
-import android.preference.PreferenceManager;
 import android.provider.ContactsContract;
 import android.provider.ContactsContract.Groups;
 import android.provider.ContactsContract.Settings;
@@ -81,13 +81,13 @@
         LoaderCallbacks<CustomContactListFilterActivity.AccountSet> {
     private static final String TAG = "CustomContactListFilterActivity";
 
+    public static final String EXTRA_CURRENT_LIST_FILTER_TYPE = "currentListFilterType";
+
     private static final int ACCOUNT_SET_LOADER_ID = 1;
 
     private ExpandableListView mList;
     private DisplayAdapter mAdapter;
 
-    private SharedPreferences mPrefs;
-
     @Override
     protected void onCreate(Bundle icicle) {
         super.onCreate(icicle);
@@ -111,7 +111,6 @@
             }
         });
 
-        mPrefs = PreferenceManager.getDefaultSharedPreferences(this);
         mAdapter = new DisplayAdapter(this);
 
         mList.setOnCreateContextMenuListener(this);
@@ -837,6 +836,20 @@
         }
     }
 
+    private boolean hasUnsavedChanges() {
+        if (mAdapter == null || mAdapter.mAccounts == null) {
+            return false;
+        }
+        if (getCurrentListFilterType() != ContactListFilter.FILTER_TYPE_CUSTOM) {
+            return true;
+        }
+        final ArrayList<ContentProviderOperation> diff = mAdapter.mAccounts.buildDiff();
+        if (diff.isEmpty()) {
+            return false;
+        }
+        return true;
+    }
+
     @SuppressWarnings("unchecked")
     private void doSaveAction() {
         if (mAdapter == null || mAdapter.mAccounts == null) {
@@ -933,9 +946,7 @@
     public boolean onOptionsItemSelected(MenuItem item) {
         switch (item.getItemId()) {
             case android.R.id.home:
-                // Pretend cancel.
-                setResult(Activity.RESULT_CANCELED);
-                finish();
+                confirmFinish();
                 return true;
             case R.id.menu_save:
                 this.doSaveAction();
@@ -945,4 +956,47 @@
         }
         return super.onOptionsItemSelected(item);
     }
+
+    @Override
+    public void onBackPressed() {
+        confirmFinish();
+    }
+
+    private void confirmFinish() {
+        // Prompt the user whether they want to discard there customizations unless
+        // nothing will be changed.
+        if (hasUnsavedChanges()) {
+            new ConfirmNavigationDialogFragment().show(getFragmentManager(),
+                    "ConfirmNavigationDialog");
+        } else {
+            setResult(RESULT_CANCELED);
+            finish();
+        }
+    }
+
+    private int getCurrentListFilterType() {
+        return getIntent().getIntExtra(EXTRA_CURRENT_LIST_FILTER_TYPE,
+                ContactListFilter.FILTER_TYPE_ALL_ACCOUNTS);
+    }
+
+    public static class ConfirmNavigationDialogFragment
+            extends DialogFragment implements DialogInterface.OnClickListener {
+
+        @Override
+        public Dialog onCreateDialog(Bundle savedInstanceState) {
+            return new AlertDialog.Builder(getActivity(), getTheme())
+                    .setMessage(R.string.leave_customize_confirmation_dialog_message)
+                    .setNegativeButton(android.R.string.no, null)
+                    .setPositiveButton(android.R.string.yes, this)
+                    .create();
+        }
+
+        @Override
+        public void onClick(DialogInterface dialogInterface, int i) {
+            if (i == DialogInterface.BUTTON_POSITIVE) {
+                getActivity().setResult(RESULT_CANCELED);
+                getActivity().finish();
+            }
+        }
+    }
 }
diff --git a/src/com/android/contacts/group/GroupNameEditDialogFragment.java b/src/com/android/contacts/group/GroupNameEditDialogFragment.java
index b2bfd0b..36a4710 100644
--- a/src/com/android/contacts/group/GroupNameEditDialogFragment.java
+++ b/src/com/android/contacts/group/GroupNameEditDialogFragment.java
@@ -25,9 +25,8 @@
 import android.content.Intent;
 import android.content.Loader;
 import android.database.Cursor;
-import android.net.Uri;
 import android.os.Bundle;
-import android.provider.ContactsContract;
+import android.provider.ContactsContract.Groups;
 import android.support.design.widget.TextInputLayout;
 import android.support.v7.app.AlertDialog;
 import android.text.Editable;
@@ -273,16 +272,27 @@
     @Override
     public Loader<Cursor> onCreateLoader(int id, Bundle args) {
         // Only a single loader so id is ignored.
-        return new CursorLoader(getActivity(), GroupNameQuery.URI,
-                GroupNameQuery.PROJECTION, GroupNameQuery.getSelection(mAccount),
-                GroupNameQuery.getSelectionArgs(mAccount), null);
+        return new CursorLoader(getActivity(), Groups.CONTENT_SUMMARY_URI,
+                new String[] { Groups.TITLE, Groups.SYSTEM_ID, Groups.ACCOUNT_TYPE,
+                        Groups.SUMMARY_COUNT, Groups.GROUP_IS_READ_ONLY},
+                getSelection(), getSelectionArgs(), null);
     }
 
     @Override
     public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
         mExistingGroups = new HashSet<>();
+        final GroupUtil.GroupsProjection projection = new GroupUtil.GroupsProjection(data);
         while (data.moveToNext()) {
-            mExistingGroups.add(data.getString(GroupNameQuery.TITLE));
+            final String title = projection.getTitle(data);
+            // Empty system groups aren't shown in the nav drawer so it would be confusing to tell
+            // the user that they already exist. Instead we allow them to create a duplicate
+            // group in this case. This is how the web handles this case as well (it creates a
+            // new non-system group if a new group with a title that matches a system group is
+            // create).
+            if (projection.isEmptyFFCGroup(data)) {
+                continue;
+            }
+            mExistingGroups.add(title);
         }
     }
 
@@ -290,38 +300,6 @@
     public void onLoaderReset(Loader<Cursor> loader) {
     }
 
-    /**
-     * Defines the structure of the query performed by the CursorLoader created by
-     * GroupNameEditDialogFragment
-     */
-    private static class GroupNameQuery {
-
-        public static final int TITLE = 0;
-        public static final Uri URI = ContactsContract.Groups.CONTENT_URI;
-        public static final String[] PROJECTION = new String[] { ContactsContract.Groups.TITLE };
-
-        public static String getSelection(AccountWithDataSet account) {
-            final StringBuilder builder = new StringBuilder();
-            builder.append(ContactsContract.Groups.ACCOUNT_NAME).append("=? AND ")
-                    .append(ContactsContract.Groups.ACCOUNT_TYPE).append("=?");
-            if (account.dataSet != null) {
-                builder.append(" AND ").append(ContactsContract.Groups.DATA_SET).append("=?");
-            }
-            return builder.toString();
-        }
-
-        public static String[] getSelectionArgs(AccountWithDataSet account) {
-            final int len = account.dataSet == null ? 2 : 3;
-            final String[] args = new String[len];
-            args[0] = account.name;
-            args[1] = account.type;
-            if (account.dataSet != null) {
-                args[2] = account.dataSet;
-            }
-            return args;
-        }
-    }
-
     private void showInputMethod(View view) {
         final InputMethodManager imm = (InputMethodManager) getActivity().getSystemService(
                 Context.INPUT_METHOD_SERVICE);
@@ -352,4 +330,27 @@
         return mGroupNameEditText == null || mGroupNameEditText.getText() == null
                 ? null : mGroupNameEditText.getText().toString();
     }
+
+    private String getSelection() {
+        final StringBuilder builder = new StringBuilder();
+        builder.append(Groups.ACCOUNT_NAME).append("=? AND ")
+               .append(Groups.ACCOUNT_TYPE).append("=? AND ")
+               .append(Groups.DELETED).append("=?");
+        if (mAccount.dataSet != null) {
+            builder.append(" AND ").append(Groups.DATA_SET).append("=?");
+        }
+        return builder.toString();
+    }
+
+    private String[] getSelectionArgs() {
+        final int len = mAccount.dataSet == null ? 3 : 4;
+        final String[] args = new String[len];
+        args[0] = mAccount.name;
+        args[1] = mAccount.type;
+        args[2] = "0"; // Not deleted
+        if (mAccount.dataSet != null) {
+            args[3] = mAccount.dataSet;
+        }
+        return args;
+    }
 }
diff --git a/src/com/android/contacts/group/GroupUtil.java b/src/com/android/contacts/group/GroupUtil.java
index fd8c03d..eae0217 100644
--- a/src/com/android/contacts/group/GroupUtil.java
+++ b/src/com/android/contacts/group/GroupUtil.java
@@ -219,4 +219,77 @@
         }
         return array;
     }
+
+    /**
+     * Stores column ordering for the projection of a query of ContactsContract.Groups
+     */
+    public static final class GroupsProjection {
+        public final int groupId;
+        public final int title;
+        public final int summaryCount;
+        public final int systemId;
+        public final int accountName;
+        public final int accountType;
+        public final int dataSet;
+        public final int autoAdd;
+        public final int favorites;
+        public final int isReadOnly;
+        public final int deleted;
+
+        public GroupsProjection(Cursor cursor) {
+            groupId = cursor.getColumnIndex(Groups._ID);
+            title = cursor.getColumnIndex(Groups.TITLE);
+            summaryCount = cursor.getColumnIndex(Groups.SUMMARY_COUNT);
+            systemId = cursor.getColumnIndex(Groups.SYSTEM_ID);
+            accountName = cursor.getColumnIndex(Groups.ACCOUNT_NAME);
+            accountType = cursor.getColumnIndex(Groups.ACCOUNT_TYPE);
+            dataSet = cursor.getColumnIndex(Groups.DATA_SET);
+            autoAdd = cursor.getColumnIndex(Groups.AUTO_ADD);
+            favorites = cursor.getColumnIndex(Groups.FAVORITES);
+            isReadOnly = cursor.getColumnIndex(Groups.GROUP_IS_READ_ONLY);
+            deleted = cursor.getColumnIndex(Groups.DELETED);
+        }
+
+        public GroupsProjection(String[] projection) {
+            List<String> list = Arrays.asList(projection);
+            groupId = list.indexOf(Groups._ID);
+            title = list.indexOf(Groups.TITLE);
+            summaryCount = list.indexOf(Groups.SUMMARY_COUNT);
+            systemId = list.indexOf(Groups.SYSTEM_ID);
+            accountName = list.indexOf(Groups.ACCOUNT_NAME);
+            accountType = list.indexOf(Groups.ACCOUNT_TYPE);
+            dataSet = list.indexOf(Groups.DATA_SET);
+            autoAdd = list.indexOf(Groups.AUTO_ADD);
+            favorites = list.indexOf(Groups.FAVORITES);
+            isReadOnly = list.indexOf(Groups.GROUP_IS_READ_ONLY);
+            deleted = list.indexOf(Groups.DELETED);
+        }
+
+        public String getTitle(Cursor cursor) {
+            return cursor.getString(title);
+        }
+
+        public long getId(Cursor cursor) {
+            return cursor.getLong(groupId);
+        }
+
+        public String getSystemId(Cursor cursor) {
+            return cursor.getString(systemId);
+        }
+
+        public int getSummaryCount(Cursor cursor) {
+            return cursor.getInt(summaryCount);
+        }
+
+        public boolean isEmptyFFCGroup(Cursor cursor) {
+            if (accountType == -1 || isReadOnly == -1 ||
+                    systemId == -1 || summaryCount == -1) {
+                throw new IllegalArgumentException("Projection is missing required columns");
+            }
+            return GoogleAccountType.ACCOUNT_TYPE.equals(cursor.getString(accountType))
+                    && cursor.getInt(isReadOnly) != 0
+                    && isSystemIdFFC(cursor.getString(systemId))
+                    && cursor.getInt(summaryCount) <= 0;
+        }
+    }
 }
\ No newline at end of file