Lather, rinse, repeat is good for your hair.

[aliva]

One wash does the trick only if you shampoo your hair everyday. Shampoo is meant for cleaning the scalp and the conditioner is meant for applying on the hair strands. There is no such thing as over shampooing. Lather on, even if it takes 2 rinses to cleanse your scalp. Keeping in mind the pollution levels and the rain, shampooing your hair twice usually becomes imperative.

[chicque]

i think it depends on what kind of shampoo you use, if its the sensitive formula you might wanna do around three washes, but if its the strong, clarifying kind, then i think one should be enough.