Guy R. Powell

Guy's Marketing Books

Guy R. Powell is a marketing strategist and author helping marketers drive revenue through smarter decisions and analytics.

His newest book, AI Marketing Machine (June 16, 2026), is a practical guide to harnessing AI for marketing strategy and results. He has also authored Marketing Machine, Marketing Calculator, and ROI of Social Media — the latter two with John Wiley & Sons.

Guy is President and Founder of ProRelevant, a global analytics and consulting firm with offices in Atlanta, Charlotte, Singapore, and Bangalore.

Guy's Historical Fiction Books

Guy is also a part-time historian, Christian, and author of The Only Witness: A History of the Shroud of Turin — a fast-paced Christian fiction tracing the remarkable journey of the Shroud from Jerusalem to Turin, weaving history, science, and faith into a compelling story.