Markey is also the co-creator of the Net Promoter System of management (NPS), along with fellow Bain & Company consultant Fred Reichheld.

[11][12] His most recent book, The Ultimate Question 2.0: How Net Promoter Companies Thrive in a Customer-Driven World,[13] was a New York Times Bestseller[14] and co-authored by long-time collaborator, Fred Reichheld of Bain & Company.

The book focuses on Net Promoter Score (NPS), a concept Reichheld developed based on his research in measuring customer satisfaction, customer retention and its link to revenue growth and profitability.

[16] Markey is also a professor at Harvard Business School, where he teaches an MBA course in managing service operations.

He serves on the board of directors for AI-based customer support technology company Forethought.