I have fine thin hair and this truly does nothing. A waste of money.

I agree with bubblegum83. I have very thick hair in general, but after a horrible chemical process I was left with very thin/bald patches right on my hairline making my face shape resemble a light bulb when I pulled my hair back. When the hair did grow in it was baby fine and you could still see some skin.and lighter looking. After using this it is back to its normal thickness and color and looks great! However, I don't think it would work on normal fine hair because there is a genetic limit to thickness. It's amazing for those left in dire condition from some chemical process though!

Because I have fine blond hair and not that much of it, I am a sucker for a product with the word "thickening" in its title. This product, B&B Thickening Serum, does absolutely nothing to "thicken" my hair. It's a total waste of money in a cute little bottle. To paraphrase B&B, it's useless (really). If I didn't feel so dumb for buying it, I'd take it back to Sephora but I'm going to leave it on my bathroom shelf so it serves as a daily reminder to NOT buy stuff on the spur of the moment. continued >>

This product actually seems to work for me. After I've shampooed and towel dried my hair, I will rub the serum into the temples, where the hair is lesser, then run through my fingers through the rest of my long hair. There doesn't seem to be such a severe "bald spot" when I pull my hair back into a tight pony tail.
It's a watery yellow serum that dries up very quickly when you pump into your palm.
It is quite expensive considering the quantity, so I wouldn't recommend using all the product throughout the entire head or hair. It is probably best for people who have mild "balding" problem. continued >>