According to Dr. Queller, oily hair types absolutely should use a conditioner after shampooing their hair. A traditional liquid shampoo for oily hair can assist with absorbing oil without leaving any residue like a dry shampoo (which, to reiterate, doesn’t actually cleanse), making it one of the best first steps you can take to minimize oiliness. For our list of the best shampoos and conditioners for oily hair, we considered each product's performance across five primary categories: product ingredients and efficacy, packaging, fragrance, texture, and results.