My DH has a very sensitive scalp too. We use MooGoo shampoo. It's so mild that technically you can drink it (but they say it tastes bad LOL) Check out their web site it's very informative. Quite a few BB members have tried it now (I found out about it here in BB last year and haven't needed anything else). Oh and it smells divine! And it lathers properly but doesn't contain SFSs.