From what i know acne can continue on into adulthood (which is annoying.) There can be many different causes for it (from what i have been told): hormones, genetics and bacteria under your skin. Luckily, there are many treatments you can use, and from experience treatments that contain benoxide peroxide or salicylic acid can help out with acne. If it gets really bad though you can always have a visit to the doctors as they can offer some advise and treatments.