diff --git a/doc/emacs/files.texi b/doc/emacs/files.texi
index 46e64c2a27..e4a1369a74 100644
--- a/doc/emacs/files.texi
+++ b/doc/emacs/files.texi
@@ -250,7 +250,7 @@ Visiting
 @end group
 @end example
 
-  With a prefix argument @kbd{C-u}, the meaning of
+  With a prefix argument @kbd{C-x &}, the meaning of
 @code{find-file-asynchronously} will be reverted.  If this user option
 is @code{nil}, visiting a file is performed asynchronously.  Contrary,
 if this user option is address@hidden, visiting a file is performed
diff --git a/doc/lispref/files.texi b/doc/lispref/files.texi
index 9faa47b455..54737ebe64 100644
--- a/doc/lispref/files.texi
+++ b/doc/lispref/files.texi
@@ -119,7 +119,7 @@ Visiting Functions
 If @var{async} is address@hidden, the file will be loaded into the
 buffer asynchronously.  Interactively, this is indicated by either
 setting user option @code{find-file-asynchronously} to address@hidden,
-or by a prefix argument.
+or by a prefix argument @kbd{C-x &}.
 
 When @code{find-file} is called interactively, it prompts for
 @var{filename} in the minibuffer.
@@ -232,8 +232,8 @@ Visiting Functions
 If this variable is address@hidden, a file will be visited
 asynchronously when called interactively.  If it is a regular
 expression, it must match the file name to be visited.  This behavior
-is toggled by a prefix argument to the interactive call of the file
-visiting command.
+is toggled by a prefix argument @kbd{C-x &} to the interactive call of
+the file visiting command.
 @end defopt
 
 @defopt find-file-hook
diff --git a/lisp/files.el b/lisp/files.el
index 195694a7b6..ccdbaeb315 100644
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -1576,14 +1576,56 @@ minibuffer-with-setup-hook
              ,@body)
          (remove-hook 'minibuffer-setup-hook ,hook)))))
 
+(defun universal-file-visiting-argument (async)
+  "Execute a file visiting or saving command using the ASYNC argument.
+See `find-file-asynchronously' for valid values of ASYNC."
+  (interactive
+   (list (and (featurep 'threads) (not find-file-asynchronously))))
+  (let* ((find-file-asynchronously async)
+         (keyseq (read-key-sequence (format "Command to visit or save file:")))
+	 (cmd (key-binding keyseq))
+	 prefix)
+    ;; `read-key-sequence' ignores quit, so make an explicit check.
+    ;; Like many places, this assumes quit == C-g, but it need not be.
+    (if (equal last-input-event ?\C-g)
+	(keyboard-quit))
+    (when (memq cmd '(universal-argument digit-argument))
+      (call-interactively cmd)
+
+      ;; Process keys bound in `universal-argument-map'.
+      (while (progn
+	       (setq keyseq (read-key-sequence nil t)
+		     cmd (key-binding keyseq t))
+	       (not (eq cmd 'universal-argument-other-key)))
+	(let ((current-prefix-arg prefix-arg)
+	      ;; Have to bind `last-command-event' here so that
+	      ;; `digit-argument', for instance, can compute the
+	      ;; prefix arg.
+	      (last-command-event (aref keyseq 0)))
+	  (call-interactively cmd)))
+
+      ;; This is the final call to `universal-argument-other-key', which
+      ;; set's the final `prefix-arg.
+      (let ((current-prefix-arg prefix-arg))
+	(call-interactively cmd))
+
+      ;; Read the command to execute with the given prefix arg.
+      (setq prefix prefix-arg
+	    keyseq (read-key-sequence nil t)
+	    cmd (key-binding keyseq)))
+
+    (let ((current-prefix-arg prefix))
+      (message "")
+      (call-interactively cmd))))
+
+(define-key ctl-x-map "&" 'universal-file-visiting-argument)
+
 (defun find-file-read-args (prompt mustmatch &optional wildcards)
   "Return the interactive spec (<filename> <async>).
 If WILDCARDS is non-nil, return the spec (<filename> t <async>)."
   (let ((filename (read-file-name prompt nil default-directory mustmatch))
-        (async (and (xor find-file-asynchronously current-prefix-arg)
-                    (featurep 'threads))))
-    (when (and async (stringp find-file-asynchronously))
-      (setq async (string-match-p find-file-asynchronously filename)))
+        (async (and (featurep 'threads) find-file-asynchronously)))
+    (when (stringp async) (setq async (string-match-p async filename)))
     (if wildcards `(,filename t ,async) `(,filename ,async))))
 
 (defmacro find-file-with-threads (filename async &rest body)
@@ -1794,8 +1836,8 @@ find-alternate-file-other-window
        (list (read-file-name
 	      "Find alternate file: " file-dir nil
               (confirm-nonexistent-file-or-buffer) file-name)
-	     t (and (xor find-file-asynchronously current-prefix-arg)
-                    (featurep 'threads))))))
+	     t (and (featurep 'threads) find-file-asynchronously)))))
+  (when (stringp async) (setq async (string-match-p async filename)))
   (if (one-window-p)
       (find-file-other-window filename wildcards async)
     (save-selected-window
@@ -1839,8 +1881,8 @@ find-alternate-file
      (list (read-file-name
 	    "Find alternate file: " file-dir nil
             (confirm-nonexistent-file-or-buffer) file-name)
-	   t (and (xor find-file-asynchronously current-prefix-arg)
-                  (featurep 'threads)))))
+	   t (and (featurep 'threads) find-file-asynchronously))))
+  (when (stringp async) (setq async (string-match-p async filename)))
   (unless (run-hook-with-args-until-failure 'kill-buffer-query-functions)
     (user-error "Aborted"))
   (and (buffer-modified-p) buffer-file-name