It used to be that sussing out a great shampoo meant surreptitiously removing the cap in the store and giving it a little sniff. Today, an amazing fragrance, great texture—these are simply table stakes. Consumers expect more from their products; they read the labels and want to know which ingredients really work, says L.A.-based stylist David Lopez. As a result, he adds, “we’re seeing more brands based in the science of hair care. It’s not just about looking pretty.”