I have noticed while using the proactive system. The best prouct in my starter kit was the refining mask. I never knew sulfer was an acne fighting agent till i recieved this product. It was really gentle on my skin and it never made my skin asdry as other products i have used.So, after using the exfoliating cleanser i used the mask and noticed a huge change in my complexion. My skin was brighter and clearer. The redness in my face from me "picking", instantly dissapeared. I loved this product the most, especially before a big date or going out with the girls, I just wash my face use the mask, rinse...