Book excerpt: New research indicates that microbiota make us who we are. The skin's ecosystem is inhabited by diverse microorganisms, most of which are harmless or even beneficial. A few are pathogenic and play a role in acne formation. The Acne Answer looks at treating inflammatory skin conditions such as teenage acne, adult acne and rosacea from the natural and organic perspective. It covers the whys and wherefores of how acne is formed and what can be done to improve problem skin based on scientific research.