This chapter is an adaptation of a Harvard Business School case on Booking.com, a leader in online experimentation. It explores how the company's goal is to better understand its customers, achieved through experimentation at all levels and by all team members. It notes how even the simplest A/B experiments have contributed to their ability to better appeal to their consumers. The author discusses how experimentation, combined with other measurable data such as KPIs, is far more valuable than attempting to intuit what customers want. Booking.com's experimental process is explored, empathizing how it is most effective to have one overarching goal that can be approached from multiple angles. This approach enables all teams across all departments to engage in coordinated and transparent experimentation toward a common objective. The way the company is organized-from its leadership and interactions with other businesses to its policies, values, and culture-is all designed with the understanding that it is an experimental organization. This deep commitment to experimentation is a key factor to what makes them so successful at it.