diff --git a/doc/auctex.texi b/doc/auctex.texi
index 8a1fc1a..4156a0b 100644
--- a/doc/auctex.texi
+++ b/doc/auctex.texi
@@ -1107,6 +1107,19 @@ This can be stopped by entering @code{LaTeX-math-mode},
 If non-nil, append a empty pair of braces after inserting a macro.
 @end defopt
 
+@defopt TeX-insert-braces-alist
+Control the insertion of a pair of braces after a macro on a per macro
+basis.
+
+This variable is an alist.  Each element is a cons cell, whose car is
+the macro name, and the cdr is non-nil or nil, depending on whether a
+pair of braces should be, respectively, appended or not to the macro.
+
+If a macro has an element in this variable, @code{TeX-parse-macro} will
+use its value to decided what to do, whatever the value of the variable
+@code{TeX-insert-braces}.
+@end defopt
+
 Completions work because @AUCTeX{} can analyze @TeX{} files, and store
 symbols in Emacs Lisp files for later retrieval.  @xref{Automatic}, for
 more information.
diff --git a/doc/changes.texi b/doc/changes.texi
index a7ed8db..df69cb4 100644
--- a/doc/changes.texi
+++ b/doc/changes.texi
@@ -30,8 +30,8 @@ Completion for class options of the standard @LaTeX{} classes is
 provided as well.
 
 @item
-New user option @code{LaTeX-default-author}.  It is used as initial
-input to @kbd{C-c RET author RET}.
+New user options @code{LaTeX-default-author} and
+@code{TeX-insert-braces-alist}.
 
 @item
 @samp{biblatex} support was greatly expanded.  If parsing is enabled,
diff --git a/style/booktabs.el b/style/booktabs.el
index e126872..ee19459 100644
--- a/style/booktabs.el
+++ b/style/booktabs.el
@@ -1,6 +1,6 @@
 ;;; booktabs.el -- AUCTeX style for booktabs.sty
 
-;; Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+;; Copyright (C) 2003, 2004, 2013 Free Software Foundation, Inc.
 
 ;; Author:   Ralf Angeli <angeli@iwi.uni-sb.de>
 ;; Maintainer: auctex-devel@gnu.org
@@ -34,23 +34,27 @@
   "Prompt for a value and use parentheses when it is inserted.
 If OPTIONAL is non-nil the parameter is labeled as optional.
 PROMPT is the value of the prompt to be shown."
-  (let ((< "\(")
-	(> "\)"))
+  (let ((TeX-arg-opening-brace "\(")
+	(TeX-arg-closing-brace "\)"))
     (TeX-parse-argument optional prompt)))
 
 (TeX-add-style-hook
  "booktabs"
  (lambda ()
-
+   ;; Do not append an empty group to toprule, midrule, and bottomrule macros,
+   ;; otherwise one gets a wrong spacing in the table.
+   (setq TeX-insert-braces-alist (append TeX-insert-braces-alist
+					 '(("toprule" . nil)
+					   ("midrule" . nil)
+					   ("bottomrule" . nil))))
    ;; New symbols
    (TeX-add-symbols
     '("toprule" [ "Thickness" ])
     '("midrule" [ "Thickness" ])
     '("bottomrule" [ "Thickness" ])
-    ;; FIXME: The qestion for the trim parameter will only be asked if
-    ;; a value for the thickness parameter was given.  Is this a
-    ;; feature of `TeX-parse-arguments'?
-    '("cmidrule" [ "Thickness" ] [ LaTeX-booktabs-arg-paren "Trim" ]
+    ;; The `ignore' resets `last-optional-rejected' to nil so that the trim
+    ;; argument is prompted also when the thickness is skipped.
+    '("cmidrule" [ "Thickness" ] (ignore) [ LaTeX-booktabs-arg-paren "Trim" ]
       "Column(s)")
     '("addlinespace" [ "Height" ])
     '("morecmidrules")
@@ -69,6 +73,6 @@ PROMPT is the value of the prompt to be shown."
 			      'function))))
 
 (defvar LaTeX-booktabs-package-options nil
-  "Package options for the booktabs package.")			
+  "Package options for the booktabs package.")
 
 ;;; booktabs.el ends here
diff --git a/tex.el b/tex.el
index 66e22cd..1ab9647 100644
--- a/tex.el
+++ b/tex.el
@@ -2587,10 +2587,27 @@ Or alternatively:
 (make-variable-buffer-local 'TeX-default-macro)
 
 (defcustom TeX-insert-braces t
-  "*If non-nil, append a empty pair of braces after inserting a macro."
+  "*If non-nil, append a empty pair of braces after inserting a macro.
+
+See also `TeX-insert-braces-alist'."
   :group 'TeX-macro
   :type 'boolean)
 
+(defcustom TeX-insert-braces-alist nil
+  "Alist of macros to which braces should or should not be appended.
+
+Each element is a cons cell, whose CAR is the macro name, and the
+CDR is non-nil or nil, depending on whether a pair of braces
+should be, respectively, appended or not to the macro.
+
+If a macro has an element in this variable, `TeX-parse-macro'
+will use its value to decided what to do, whatever the value of
+the variable `TeX-insert-braces'."
+  :group 'TeX-macro
+  :type '(repeat (cons (string :tag "Macro name")
+		       (boolean :tag "Append braces?"))))
+(make-variable-buffer-local 'TeX-insert-braces-alist)
+
 (defcustom TeX-insert-macro-default-style 'show-optional-args
   "Specifies whether `TeX-insert-macro' will ask for all optional arguments.
 
@@ -2713,13 +2730,19 @@ type of ARGS:
     (cond ((marker-position exit-mark)
 	   (goto-char (marker-position exit-mark))
 	   (set-marker exit-mark nil))
-	  ((and TeX-insert-braces
-		;; Do not add braces if the argument is 0 or -1.
-		(not (and (= (safe-length args) 1)
-			  (numberp (car args))
-			  (<= (car args) 0)))
-		(equal position (point))
-		(string-match "[a-zA-Z]+" symbol))
+	  ((let ((element (assoc symbol TeX-insert-braces-alist)))
+	     ;; If in `TeX-insert-braces-alist' there is an element associated
+	     ;; to the current macro, use its value to decide whether inserting
+	     ;; a pair of braces, otherwise use the standard criterion.
+	     (if element
+		 (cdr element)
+	       (and TeX-insert-braces
+		    ;; Do not add braces if the argument is 0 or -1.
+		    (not (and (= (safe-length args) 1)
+			      (numberp (car args))
+			      (<= (car args) 0)))
+		    (equal position (point))
+		    (string-match "[a-zA-Z]+" symbol))))
 	   (if (texmathp)
 	       (when (TeX-active-mark)
 		 (insert TeX-grop)