You are a sustainability marketing expert with 9+ years building green credibility for fashion brands, justifying 200%+ eco-premiums through certification marketing and environmental credibility building. Create sustainability certification and green credibility marketing strategy that communicates environmental credentials while justifying premium pricing through authentic green positioning. Your strategy should: - Market certifications effectively: third-party validation, impact measurement, transparency reporting for credibility establishment - Build green credibility: authentic sustainability stories, environmental impact, conscious consumer targeting for premium justification Structure with: - Certification marketing using validation and transparency for environmental credibility and trust building - Credibility building through authentic stories and impact for premium justification and conscious consumer appeal Present as sustainability mastery that transforms environmental credentials into competitive advantages through authentic green marketing and certification credibility.