Instruct: Classify the given review into positive or negative sentiment.
Query: This stuff works very well.

Over the years I've had need for this shampoo and it really works well. I found it's better than any of the other shampoos out there for dandruff or, for me, Psoriasis which also causes flaking. It's going into winter which means dry air and more outbreaks of this. I just bought another 6 bottles. If only, it was cheaper but amazon has some of the best prices. Just watch for sales and stock up.