Salicylic Acid is a beta hydroxy acid found in many plants but it's most well know source is White Willow or Salix alba from which it's name is derived. Topically, Salicylic acid is most commonly found in products used to combat acne and other skin conditions such as dandruff, callouses and warts. It acts as a comdeolytic and bateriostatic agent meaning it stimulates the shedding of dead skin cells, unclogs pores and inhibits the growth of potentially acne causing bacteria. Usage: add to the oil phase 0.5 to 1.0% for sensitive skin products 2.0% for active treatment products 50g