diff --git a/modules/book.module b/modules/book.module
index 0268329dfa08c5593ae6dd9ab68e5a32e65f1b72..a9ce5c75890a97d7ae48edc8692ae95fffb4bfe1 100644
--- a/modules/book.module
+++ b/modules/book.module
@@ -121,7 +121,7 @@ function book_block($op = 'list', $delta = 0) {
   else {
     // Only display this block when the user is browsing a book:
     if (arg(0) == 'node' && is_numeric(arg(1))) {
-      $result = db_query('SELECT n.nid, n.title, b.parent FROM {node} n '. node_access_join_sql() .' INNER JOIN {book} b ON n.nid = b.nid WHERE '. node_access_where_sql() .' n.nid = %d', arg(1));
+      $result = db_query('SELECT n.nid, n.title, b.parent FROM {node} n '. node_access_join_sql() .' INNER JOIN {book} b ON n.nid = b.nid WHERE '. node_access_where_sql() .' AND n.nid = %d', arg(1));
       if (db_num_rows($result) > 0) {
         $node = db_fetch_object($result);
 
diff --git a/modules/book/book.module b/modules/book/book.module
index 0268329dfa08c5593ae6dd9ab68e5a32e65f1b72..a9ce5c75890a97d7ae48edc8692ae95fffb4bfe1 100644
--- a/modules/book/book.module
+++ b/modules/book/book.module
@@ -121,7 +121,7 @@ function book_block($op = 'list', $delta = 0) {
   else {
     // Only display this block when the user is browsing a book:
     if (arg(0) == 'node' && is_numeric(arg(1))) {
-      $result = db_query('SELECT n.nid, n.title, b.parent FROM {node} n '. node_access_join_sql() .' INNER JOIN {book} b ON n.nid = b.nid WHERE '. node_access_where_sql() .' n.nid = %d', arg(1));
+      $result = db_query('SELECT n.nid, n.title, b.parent FROM {node} n '. node_access_join_sql() .' INNER JOIN {book} b ON n.nid = b.nid WHERE '. node_access_where_sql() .' AND n.nid = %d', arg(1));
       if (db_num_rows($result) > 0) {
         $node = db_fetch_object($result);