I've had a small problem with orgmode and auctex. Follwing the auctex quickstart I added the following to my .emacs

(setq-default TeX-master nil)

and then from the orgmode FAQ to setup reftex in orgmode I added the following

(defun org-mode-reftex-setup ()
(load-library "reftex")
(and (buffer-file-name)
       (file-exists-p (buffer-file-name))
       (reftex-parse-all))
(define-key org-mode-map (kbd "C-c )") 'reftex-citation))
(add-hook 'org-mode-hook 'org-mode-reftex-setup)

With both of these, whenever I opened an org file I was asked to name the master file. If I comment out the setq-default I don't get the behaviour I would like with mulitfile tex files. My solution was to change

(setq-default TeX-master nil)

to

(add-hook 'TeX-mode-hook (lambda ()
               (setq-default TeX-master nil)))

I then appear to get the behaviour I desire. Is this a good way to do this? If so I might add it to the FAQ.

Cheers
Chris.