Douglas Preston Aesthetician, Business Consultant, Educator and Lecturer Douglas Preston is a business consultant and frequent lecturer in the day and medical spa industry. Preston's business articles frequently appear in DERMASCOPE Magazine, Spa Management Journal, American Spa, MedicalSpa Magazine, Les Nouvelles Esthetiques, and others. Preston is a past-president of Aesthetics International Association (AIA), and served as committee chairman for The Day Spa Association (DSA). He…